A proton and a deuteron are moving with equal velocities perpendicular to a uniform magnetic field. A deuteron has the same charge as the proton but has twice its mass. The ratio of the magnetic force on the proton to that on the deuteron is:

a. 0.5.
b. 1.
c. 2.
d. There is no magnetic force in this case.

Answers

Answer 1

Answer:

option (b)

Explanation:

mass of proton, mp = m

mass of deuteron, md = 2m

charge on proton, qp = q

charge on deuteron, qd = q

The magnetic force on the charged particle when it is moving is given by

F = q v B Sinθ

where, θ is the angle between the velocity and magnetic field.

Here, θ = 90°

Let v is the velocity of both the particle when they enters in the magnetic field.

The force on proton is given by

Fp = q x v x B ...... (1)

The force on deuteron is

Fd = q x v x B .... (2)

Divide equation (1) by equation (2)

Fp / Fd = 1

Thus, the ratio of force on proton to the force on deuteron is 1 : 1.

Thus, option (b) is correct.


Related Questions

Suppose the Earth orbited the Sun in 4 months rather than 1 year, but had exactly the samerotation speed. How much longer would a solar day be than a sidereal day? Mercury’s siderealday is 58.6 days and its orbital period is 88 days. What is the length of Mercury’s solar day?

Answers

Answer:

A) 0.1955 days

B) 35.18 days

Explanation: Given that the Earth orbited the Sun in 4 months rather than 1 year, but had exactly the same rotation speed. That is the orbital period will be

365.24/12 = P/4

P = 121.75 days

We have three periods, the orbital period Po = 121.75 days,

the sidereal period Ps = 23.93419 hours and

The mean solar day Pd =24 hours.

Since they had exactly the same rotation speed, the number of solar days in a year is Po/Pd.

The number of sidereal days in a year would be Po/Pd + 1 = 121.75 + 1 = 122.75 days. Since there are more sidereal days in a year this means that the sidereal day is a little bit shorter, 121.75/122.75 = 0.99185 times shorter.

0.99185 × 24 = 23.80448 hours.

24 - 23.80448 = 0.1955 days

Therefore, solar day is 0.99185 days longer than a sidereal day

Given that the Mercury’s side real day is 58.6 days and its orbital period is 88 days. What is the length of Mercury’s solar day?

Using the formula

Ld = PoPs/(Po + Ps)

Ld = Length of Mercury's solar day

Po = orbital period

Ps = Mercury's side real day

Ld = (88 × 58.6)/ (88 + 58.6)

Ld = 5156.8/146.6

Ld = 35.18 days

Preparing an Accounts Payable Schedule Pilsner Inc. purchases raw materials on account for use in production. The direct materials ected purchases April May June Pilsner typically pays 25% on account in the month of billing and 75% the next month Required: 1. How much cash is required for payments on account in May? $374,400 411,200 416,000 2. How much cash is expected for payments on account in June?

Answers

Answer:

How much cash is expected for payments on account in June? = $412,400.

Explanation:

Cash Required for expected payments on account in June

Pilsner Inc. pays 25% on account in the month of billing and the remaining 75% in the next month, therefore, for the month of June the total payment will include 75% of Purchases made in May and 25% of purchases made in June.

Purchases in May = $411,200

Purchases in June = $416,000

Total Payment for May = (75% of 411,200)+(25% of 416,000)

= $308,400 + $104,000

= $412,400.

What direction does a S wave move

Answers

Answer:

As they travel through rock, the waves move tiny rock particles back and forth -- pushing them apart and then back together -- in line with the direction the wave is traveling. These waves typically arrive at the surface as an abrupt thud. Secondary waves (also called shear waves, or S waves) are another type of body wave

Explanation:

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Three ideal polarizing filters are stacked, with the polarizing axis of the second and third filters at 21 degrees and 61 degrees, respectively, to that of the first. If unpolarized light is incident on the stack, the light has intensity 60.0 w/cm^ 2 after it passes through the stack.
If the incident intensity is kept constant:
1) What is the intensity of the light after it has passed through the stack if the second polarizer is removed?
2) What is the intensity of the light after it has passed through the stack if the third polarizer is removed?

Answers

Answer:

1

When second polarizer is removed the intensity after it passes through the stack is    

                    [tex]I_f_3 = 27.57 W/cm^2[/tex]

2 When third  polarizer is removed the intensity after it passes through the stack is    

                [tex]I_f_2 = 102.24 W/cm^2[/tex]

Explanation:

  From the question we are told that

       The angle of the second polarizing to the first is  [tex]\theta_2 = 21^o[/tex]  

        The angle of the third  polarizing to the first is     [tex]\theta_3 = 61^o[/tex]

        The unpolarized light after it pass through the polarizing stack   [tex]I_u = 60 W/cm^2[/tex]

Let the initial intensity of the beam of light before polarization be [tex]I_p[/tex]

Generally when the unpolarized light passes through the first polarizing filter the intensity of light that emerges is mathematically evaluated as

                     [tex]I_1 = \frac{I_p}{2}[/tex]

Now according to Malus’ law the  intensity of light that would emerge from the second polarizing filter is mathematically represented as

                    [tex]I_2 = I_1 cos^2 \theta_1[/tex]

                       [tex]= \frac{I_p}{2} cos ^2 \theta_1[/tex]

The intensity of light that will emerge from the third filter is mathematically represented as

                  [tex]I_3 = I_2 cos^2(\theta_2 - \theta_1 )[/tex]

                          [tex]I_3= \frac{I_p}{2}(cos^2 \theta_1)[cos^2(\theta_2 - \theta_1)][/tex]

making [tex]I_p[/tex] the subject of the formula

                  [tex]I_p = \frac{2L_3}{(cos^2 \theta [cos^2 (\theta_2 - \theta_1)])}[/tex]

    Note that [tex]I_u = I_3[/tex] as [tex]I_3[/tex] is the last emerging intensity of light after it has pass through the polarizing stack

         Substituting values

                      [tex]I_p = \frac{2 * 60 }{(cos^2(21) [cos^2 (61-21)])}[/tex]

                      [tex]I_p = \frac{2 * 60 }{(cos^2(21) [cos^2 (40)])}[/tex]

                           [tex]=234.622W/cm^2[/tex]

When the second    is removed the third polarizer becomes the second and final polarizer so the intensity of light would be mathematically evaluated as

                      [tex]I_f_3 = \frac{I_p}{2} cos ^2 \theta_2[/tex]

[tex]I_f_3[/tex] is the intensity of the light emerging from the stack

                     

substituting values

                     [tex]I_f_3 = \frac{234.622}{2} * cos^2(61)[/tex]

                       [tex]I_f_3 = 27.57 W/cm^2[/tex]

  When the third polarizer is removed  the  second polarizer becomes the

the final polarizer and the intensity of light emerging from the stack would be  

                  [tex]I_f_2 = \frac{I_p}{2} cos ^2 \theta_1[/tex]

[tex]I_f_2[/tex] is the intensity of the light emerging from the stack

Substituting values

                  [tex]I_f_2 = \frac{234.622}{2} cos^2 (21)[/tex]

                     [tex]I_f_2 = 102.24 W/cm^2[/tex]

   

Final answer:

The intensity of light after the second polarizer is removed is 22.88 w/cm² and after the third polarizer is removed is 26.73 w/cm².

Explanation:

The intensity of light passing through a polarizing filter can be determined by Malus's Law, which states that the intensity of the transmitted light is equal to the incident light multiplied by the square of the cosine of the angle between the filters. If unpolarized light is incident on the stack, the intensity is halved after passing through the first filter.

1) When the second polarizer is removed, the angle difference will be 40 degrees (61 degrees - 21 degrees). Hence, the intensity would be (60/2) * cos²(40 degree) = 22.88 w/cm².

2) When the third polarizer is removed, the angle difference is only 21 degrees, hence the intensity would be (60/2) * cos²(21 degree) = 26.73 w/cm².

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Space satellites in the inner solar system (such as those in orbit around Earth) are often powered by solar panels. Satellites that travel into the outer solar system, however, are usually powered by the decay of nuclear isotopes – a more expensive and dangerous technology. Why can’t they use solar panels as well?

a. At greater distances, sunlight is more likely to destructively interfere.
b. At greater distances, sunlight is more likely to constructively interfere.
c. At greater distances from the sun, the frequency of sunlight will be too low.
d. At greater distances from the sun, the intensity of sunlight will be too low.

Answers

Answer:

D

Explanation:

See attached file

Two very small planets orbit a much larger star. Planet A orbits the star with a period TA . Planet B orbits the star at four times the distance of planet A, but planet B is four times as massive as planet A. Assume that the orbits of both planets are approximately circular.

Planet B orbits the star with a period TB equal to

a. TA/4.
b. 16TA.
c. 8TA.
d. 4TA
d. TA

Answers

Answer:

Explanation:

Given that,

Period of Planet A around the star

Pa = Ta

Let the semi major axis of planet A from the star be

a(a) = x

Given that, the distance of Planet B from the star (i.e. it semi major axis) is 4 time that of Planet A

a(b) = 4 × a(a) = 4 × x

a(b) = 4x

Also planet B is 4 times massive as planet A

Using Kepler's law

P² ∝a³

P²/a³ = k

Where

P is the period

a is the semi major axis

Then,

Pa² / a(a)³ = Pb² / a(b)³

Pa denotes Period of Planet A and it is Pa = Ta

a(a) denoted semi major axis of planet A and it is a(a) = x

Pb is period of planet B, which is the required question

a(b) is the semimajor axis of planet B and it is a(b) = 4x

So,

Ta² / x³ = Pb² / (4x)³

Ta² / x³ = Pb² / 64x³

Cross multiply

Ta² × 64x³ = Pb² × x³

Divide both sides by x³

Ta² × 64 = Pb²

Then, Pb = √(Ta² × 64)

Pb = 8Ta

Then, the period of Planet B is eight times the period of Planet A.

The correct answer is C

Final answer:

The period of orbit for planet B is 4 times the period of orbit for planet A.

Explanation:

To determine the period of orbit for planet B, we can use Kepler's Third Law, which states that the square of the period of an orbit is proportional to the cube of its average distance from the center of attraction. Since planet B is four times the distance of planet A and four times as massive, its period will be 4^3/4^2 times that of planet A. Simplifying, this means that TB = 4 * TA, so the correct answer is d. 4TA.

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The same pipe is used to carry both air and water. For the same fluid velocity and friction factor for the air and water flows: the pressure drop for the air flow is greater than that for the water flow. the pressure drop for the air flow equals the pressure drop for the water flow. the pressure drop for the water flow is greater than that for the air flow.

Answers

Answer:

the pressure drop for the water flow is greater than that for the air flow.

Explanation:

Detailed analysis of the problem is show below.

A plane monochromatic radio wave (? = 0.3 m) travels in vacuum along the positive x-axis, with a time-averaged intensity I = 45.0 W/m2. Suppose at time t = 0, the electric field at the origin is measured to be directed along the positive y-axis with a magnitude equal to its maximum value. What is Bz, the magnetic field at the origin, at time t = 1.5 ns? Bz = I got .04800 but that answer didnt work.

Answers

Answer:

The magnetic field [tex]B_Z[/tex] [tex]= - 6.14*10^{-7} T[/tex]

Explanation:

From the question we are told that

      The wavelength is [tex]\lambda = 0.3m[/tex]

       The intensity is [tex]I = 45.0W/m^2[/tex]

       The time is [tex]t = 1.5ns = 1.5 *10^{-9}s[/tex]

Generally radiation intensity is mathematically represented as

              [tex]I = \frac{1}{2} c \epsilon_o E_o^2[/tex]

Where  c is the speed of light with a constant value of [tex]3.0 *10^8 m/s[/tex]

              [tex]E_i[/tex] is the electric field

             [tex]\epsilon_o[/tex] is the permittivity  of free space with a constant value of [tex]8.85*10^{-12} C^2 /N \cdot m^2[/tex]

 Making [tex]E_o[/tex] the subject of the formula we have

           [tex]E_i = \sqrt{\frac{2I}{c \epsilon_0} }[/tex]

      Substituting values

          [tex]E_i = \sqrt{\frac{2* 45 }{(3*10^8 * (8.85*10^{-12}) )} }[/tex]

               [tex]= 184.12 \ V/m[/tex]

Generally electric and magnetic field are related by the mathematical equation as follows

             [tex]\frac{E_i}{B_i} = c[/tex]

Where [tex]B_O[/tex] is the magnetic field

           making  [tex]B_O[/tex] the subject

                 [tex]B_i = \frac{E_i}{c}[/tex]

Substituting values

                 [tex]B_i = \frac{184.12}{3*10^8}[/tex]

                       [tex]= 6.14 *10^{-7}T[/tex]

Next is to obtain the wave number

  Generally  the wave number is mathematically represented as

                          [tex]n = \frac{2 \pi }{\lambda }[/tex]

Substituting values

                          [tex]n = \frac{2 \pi}{0.3}[/tex]

                              [tex]= 20.93 \ rad/m[/tex]

Next is to obtain the frequency

      Generally  the  frequency f is mathematically represented as

                    [tex]f = \frac{c}{\lambda}[/tex]

Substituting values

                   [tex]f = \frac{3 *10^8}{0.3}[/tex]

                      [tex]= 1*10^{9} s^{-1}[/tex]

Next is to obtain the angular velocity

                Generally  the  angular velocity  [tex]w[/tex] is mathematically represented as

                       [tex]w = 2 \pi f[/tex]

                           [tex]w = 2 \pi (1* 10^9)[/tex]

                              [tex]= 2 \pi * 10^9 rad/s[/tex]

Generally  the sinusoidal electromagnetic waves for the magnetic field B moving in the positive z direction is expressed as

                       [tex]B_z = B_i cos (nx -wt)[/tex]

Since the magnetic field is induced at the origin then the equation above is reduced to

                   [tex]B_z = B_i cos (n(0) -wt) = B_i cos ( -wt)[/tex]

x =0 because it is the origin we are considering

 Substituting values  

                      [tex]B_z = (6.14*10^{-7}) cos (- (2 \pi * 10^{9})(1.5 *10^{-9}))[/tex]

                           [tex]= - 6.14*10^{-7} T[/tex]

Particles (mass of each = 0.40 kg) are placed at the 60-cm and 100-cm marks of a meter stick of negligible mass. This rigid body is free to rotate about a frictionless pivot at the 0-cm end. The body is released from rest in the horizontal position. What is the magnitude of the initial linear acceleration of the end of the body opposite the pivot?

Answers

Answer:

12 m/s ∧2

Explanation:

The picture attached explains it all and i hope it helps. Thank you

Final answer:

To find the initial linear acceleration, calculate the initial torque due to gravity, the moment of inertia, and then apply Newton’s second law for rotation to obtain the initial angular acceleration. The initial linear acceleration can then be found by multiplying the initial angular acceleration by the length of the meter stick.

Explanation:

The question is asking for the initial linear acceleration of the end of the rigid body (meter stick) at the moment it is released.

The initial torque τ is equal to the gravitational forces acting on each particle times their respective distances from the pivot, summed up.

τ_initial = m*g*d1 + m*g*d2 = 0.4 kg * 9.8 m/s^2 * 0.6 m + 0.4 kg * 9.8 m/s^2 * 1.0 m

The moment of inertia I for the two-particle system can be calculated with the formula I = ∑mr^2 for each particle:

I = m*d1^2 + m*d2^2 = 0.4 kg * (0.6 m)^2 + 0.4 kg * (1.0 m)^2

According to Newton’s second law for rotation, the initial angular acceleration α is equal to the initial torque divided by the moment of inertia:

α = τ_initial / I

The initial linear acceleration a of the end of the body at the point opposite the pivot is equal to the product of the initial angular acceleration and the total length of the meter stick (1.0 m):

a = α * 1.0 m

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A fisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. It takes a time of 2.60 s for the boat to travel from its highest point to its lowest, a total distance of 0.630 m. The fisherman sees that the wave crests are spaced a horizontal distance of 5.50 m apart.

How much is the wavelength?

Answers

The question is incomplete! Complete question along with answer and step by step explanation is provided below.

Question:

A fisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. It takes a time of 2.60 s for the boat to travel from its highest point to its lowest, a total distance of 0.630 m. The fisherman sees that the wave crests are spaced a horizontal distance of 5.50 m apart.

How much is the wavelength?

How fast are the waves traveling ?

What is the amplitude A of wave?

Given Information:

time = t = 2.60 s

wavelength = λ  = 5.50 m

distance = d = 0.630 m

Required Information:

a)  wavelength = λ  = ?

b) speed = v = ?

c) Amplitude = A = ?

Answer:

a)  wavelength = 5.50 m

b) speed = 1.056 m/s

c) Amplitude = 0.315 m

Step-by-step explanation:

a)

It is given that wave crests are spaced a horizontal distance of 5.50 m apart that is basically the wavelength so,

λ  = 5.50 m

b)

We know that the speed of the wave is given by

v = λf

where λ is the wavelength and f is the frequency of the wave given by

f = 1/T

Where T is the period of the wave.

Since the it is given that boat takes 2.60 s to travel from its highest point to its lowest that is basically half of the period so one full period is

T = 2*2.60

T = 5.2 s

So the frequency is,

f = 1/5.2

f = 0.192 Hz

Therefore, the speed is

v = λf

v = 5.50*0.192

v = 1.056 m/s

c)

The amplitude of the wave is given by

A = d/2

where d is the distance from the highest point to the lowest, therefore, the amplitude is half of it.

A = 0.630/2

A = 0.315 m

A thin hoop is hung on a wall, supported by a horizontal nail. The hoop's mass is M=2.0 kg and its radius is R=0.6 m. What is the period of small oscillations of the hoop? Type your answer below, accurate to two decimal places, and assuming it is in seconds. [Recall that the moment of inertia of a hoop around its center is Icm=MR2.]

Answers

Answer:

Explanation:

Given that,

Mass of the thin hoop

M = 2kg

Radius of the hoop

R = 0.6m

Moment of inertial of a hoop is

I = MR²

I = 2 × 0.6²

I = 0.72 kgm²

Period of a physical pendulum of small amplitude is given by

T = 2π √(I / Mgd)

Where,

T is the period in seconds

I is the moment of inertia in kgm²

I = 0.72 kgm²

M is the mass of the hoop

M = 2kg

g is the acceleration due to gravity

g = 9.8m/s²

d is the distance from rotational axis to center of of gravity

Therefore, d = r = 0.6m

Then, applying the formula

T = 2π √ (I / MgR)

T = 2π √ (0.72 / (2 × 9.8× 0.6)

T = 2π √ ( 0.72 / 11.76)

T = 2π √0.06122

T = 2π × 0.2474

T = 1.5547 seconds

T ≈ 1.55 seconds to 2d•p

Then, the period of oscillation is 1.55seconds

Consider two pulses (a wave with only a single peak) traveling towards each other on a string. When the instant that the peaks of these two pulses cross, the resultant disturbance has a maximum displacement of 3.80 A where A is the amplitude of the first pulse. What must be the amplitude of the second pulse be

Answers

Answer:

2.8A

Explanation:

To calculate the total amplitude (when both pulses meet), we need to add up the amplitudes of each pulse. Since A is the amplitude of the first pulse, and we can call B the amplitude of the second pulse and C the total amplitude, we have that A+B=C=3.8A, which means that B=3.8A-A=2.8A, which we have already said is the amplitude of the second pulse.

An airplane is initially flying horizontally (not gaining or losing altitude), and heading exactly North. Suppose that the earth's magnetic field at this point is also exactly horizontal, and points from South to North (it really does!). The airplane now starts a different motion. It maintains the same speed, but gains altitude at a constant rate, still heading North. The magnitude of the electric potential difference between the wingtips has... [Remember that the airplane is made of metal, and is a conductor] Group of answer choices

Answers

Note: The answer choices are :

a) Increased

b) Decreased

c) stayed the same

Answer:

The correct option is Increased

The magnitude of the electric field potential difference between the wingtips increases.

Explanation:

The magnitude of the electric potential difference is the induced emf and is given by the equation:

[tex]emf = l (v \times B)[/tex]

where l = length

v = velocity

B = magnetic field

As the altitude of the airplane increases, the magnetic flux becomes stronger, the speed of the airplane becomes perpendicular to the magnetic field, i.e. [tex]v \times B = vB sin90 = vB\\[/tex] ,

the induced emf = vlB, and thus increases.

The magnitude of the electric field potential difference between the wingtips increases

21. (a) Aircraft sometimes acquire small static charges. Suppose a supersonic jet has a 0.500-μC charge and flies due west at a speed of 660. m/s over Earth’s south magnetic pole, where the 8.00 × 10−5 − T magnetic field points straight down into the ground. What are the direction and the magnitude of the magnetic force on the plane? (b) Discuss whether the value obtained in part (a) implies this is a significant or negligible effect.

Answers

Answer:

Explanation:

The picture attached shows the full explanation and i hope it helps. Thank you

Final answer:

The magnetic force on a supersonic jet with a 0.500-μC static charge, flying over the Earth's south magnetic pole at 660 m/s, is 7.50 × 10-7 N, directed to the north. This effect is considered negligible given the small magnitude of the force.

Explanation:

When an aircraft with a static charge flies through the Earth's magnetic field, it experiences a magnetic force due to the interaction between its charge, its velocity, and the magnetic field. This is a concept from electromagnetism, specifically the Lorentz force. The magnitude of the magnetic force (F) can be calculated using the equation F = qvBsin(θ), where q is the charge on the aircraft, v is the speed of the aircraft, B is the magnetic field strength, and θ is the angle between the velocity of the charge and the direction of the magnetic field.

For a supersonic jet with a 0.500-μC (or 0.500x10-6 C) charge flying due west over the Earth's south magnetic pole, where the magnetic field (B) is 8.00 × 10-5 T and points straight down (θ = 90 degrees), the magnitude of the magnetic force is:

F = (0.500x10-6 C)(660 m/s)(8.00 × 10-5 T)sin(90 degrees) = 7.50 × 10-7 N, perpendicular to both the magnetic field lines and the velocity of the jet (which means it points either north or south). Since the jet is flying due west and the magnetic field is down, the right-hand rule indicates the force will push the jet to the north.

Regarding part (b), since the magnetic force magnitude, 7.50 × 10-7 N, is quite small compared to the typical forces experienced by a supersonic jet, such as thrust, drag, and lift, it can be considered a negligible effect. It's unlikely to have any significant impact on the flight of the aircraft.

A firm wants to determine the amount of frictional torque in their current line of grindstones, so they can redesign them to be more energy efficient. To do this, they ask you to test the best-selling model, which is basically a diskshaped grindstone of mass 1.1 kg and radius 0.09 m which operates at 73.3 rad/s. When the power is shut off, you time the grindstone and find it takes 42.4 s for it to stop rotating. What is the frictional torque exerted on the grindstone in newton-meters

Answers

Explanation:

Mass of the diskshaped grindstone, m = 1.1 kg

Radius of disk, r = 0.09 m

Angular velocity, [tex]\omega=73.3\ rad/s[/tex]

Time, t = 42.4 s

We need to find the frictional torque exerted on the grindstone. Torque in the rotational kinematics is given by :

[tex]\tau=I\alpha[/tex]

I is moment of inertia of disk, [tex]I=\dfrac{mr^2}{2}[/tex]

[tex]\tau=\dfrac{mr^2\alpha }{2}\\\\\tau=\dfrac{1.1\times (0.09)^2\times 73.3 }{2\times 42.4}\\\\\tau=7.7\times 10^{-3}\ N-m[/tex]

So, the frictional torque exerted on the grindstone is  [tex]7.7\times 10^{-3}\ N-m[/tex].

o study torque experimentally, you apply a force to a beam. One end of the beam is attached to a pivot that allows the beam to rotate freely. The pivot is taken as the origin or your coordinate system. You apply a force of F = Fx i + Fy j + Fz k at a point r = rx i + ry j + rz k on the beam. show answer No Attempt 33% Part (a) Enter a vector expression for the resulting torque, in terms of the unit vectors i, j, k and the components of F and r. τ = | γ θ i j k d Fx Fy Fz g m n rx ry rz ( ) 7 8 9 HOME ↑^ ^↓ 4 5 6 ← / * 1 2 3 → + - 0 . END √() BACKSPACE DEL CLEAR Grade Summary Deductions 0% Potential 100% Submissions Attempts remaining: 3 (4% per attempt) detailed view Hints: 4% deduction per hint. Hints remaining: 2 Feedback: 5% deduction per feedback. No Attempt No Attempt 33% Part (b) Calculate the magnitude of the torque, in newton meters, when the components of the position and force vectors have the values rx = 0.76 m, ry = 0.035 m, rz = 0.015 m, Fx = 3.6 N, Fy = -2.8 N, Fz = 4.4 N. No Attempt No Attempt 33% Part (c) If the moment of inertia of the beam with respect to the pivot is I = 442 kg˙m2, calculate the magnitude of the angular acceleration of the beam about the pivot, in radians per second squared. All content © 2020 Expert TA, LLC

Answers

Answer:

(a)  Resulting torque =  (ryFz - rzFy) i +(rzFx - rxFz) j+(rxFy - ryFx) k

(b) Magnitude of resulting torque  =  = 3.99 Nm

(c) angular acceleration = = 0.009027 rad/s²

                     

Explanation:

Given Data;

I = 442 kg˙m2

rx = 0.76 m,

ry = 0.035 m,

rz = 0.015 m,

Fx = 3.6 N,

Fy = -2.8 N,

Fz = 4.4 N

F = Fx i + Fy j + Fz ------------------------------1

r =  rx i + ry j + rz k ------------------------------2

(a) Torgue is given by the formula;

T = r * F  ------------------------------------3

Putting equation 1 and 2 into equation 3, we have;

Torque= r x F

            = (rx i +ry j +rz k) x (Fx i + Fy j +Fz k )

            = (ryFz - rzFy) i +(rzFx - rxFz) j+(rxFy - ryFx) k

Therefore,

Resulting torque =  (ryFz - rzFy) i +(rzFx - rxFz) j+(rxFy - ryFx) k

b)

Putting given values into the above expression, we have

 torque =  (ryFz - rzFy) i +(rzFx - rxFz) j+(rxFy - ryFx) k

=(0.035*4.4 - (0.015*-2.8))i +(0.015*3.6 - 0.76*4.4)j+(0.76* -2.8 - 0.035*3.6)k

= (0.154 +0.041) i + (0.054 - 3.344) j + (-2.128 -0.126) k

= (0.196) i - (3.29) j + (-2.254) k

Magnitude of resulting torque = √(0.196² + 3.29² +2.254²

                                                  =√15.943031

                                                  = 3.99 Nm

c) Angular acceleration is given by the formula;

angular acceleration = torque/moment of inertia

                                   = 3.99/ 442

                                  = 0.009027 rad/s²

                     

After your school's team wins the regional championship, students go to the dorm roof and start setting off fireworks rockets. The rockets explode high in the air and the sound travels out uniformly in all directions. If the sound intensity is 1.52 10-6 W/m2 at a distance of 123 m from the explosion, at what distance from the explosion is the sound intensity half this value

Answers

Answer:

The distance when the intensity is halved is 173.95 m

Explanation:

Given;

initial intensity of the sound, I₁ = 1.52 x 10⁻⁶ W/m²

initial distance from the explosion, d₁ = 123 m

final intensity of the sound, I₂ = ¹/₂ (1.52 x 10⁻⁶ W/m²) = 0.76 x 10⁻⁶ W/m²

Intensity of sound is inversely proportional to the square of distance between the source and the receiver.

I ∝ ¹/d²

I₁d₁² = I₂d²

(1.52 x 10⁻⁶)(123)² = (0.76 x 10⁻⁶)d₂²

d₂² = (1.52 x 10⁻⁶ x 123²) / (0.76 x 10⁻⁶)

d₂² = 30258

d₂ = √30258

d₂ = 173.95 m

Therefore, the distance when the intensity is halved is 173.95 m

The sound intensity varies inversely as the square of the distance from the

explosion source.

The distance from the explosion at which the sound intensity is half of 1.52 × 10⁻⁶ W/m², is approximately 173.95 meters

Reasons:

The sound intensity at 123 m = 1.52 × 10⁻⁶ W/m²

Required:

The distance at which the sound intensity is half the given value.

Solution:

Sound intensity is given by the formula;

[tex]I \propto \mathbf{ \dfrac{1}{d^2}}[/tex]

Which gives;

I × d² = Constant

I₁ × d₁² = I₂ × d₂²

Where;

I₁ = The sound intensity at d₁

I₂ = The sound intensity at d₂

[tex]d_2 = \mathbf{ \sqrt{\dfrac{I_1 \times d_1^2}{I_2} }}[/tex]

When the sound intensity is half the given value, we have;

I₂ = 0.5 × I₁

I₂ = 0.5 × 1.52 × 10⁻⁶ = 7.6 × 10⁻⁷

Therefore;

[tex]d_2 = \sqrt{\dfrac{1.52 \times 10^{-6} \times 123^2}{7.6 \times 10^{-7}} } \approx 173.95[/tex]

The distance from the explosion at which the sound intensity is half of the

sound intensity at 123 meters from the explosion, d₂ ≈ 173.95 m.

Learn more here:

https://brainly.com/question/14695863

Review the multiple-concept example as an aid in solving this problem. In a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves on a circle. In one instance, the radius of the circle is 0.685 m. At one point on this circle, the ball has an angular acceleration of 63.8 rad/s2 and an angular speed of 15.0 rad/s. (a) Find the magnitude of the total acceleration (centripetal plus tangential) of the ball.

Answers

Answer:

Total acceleration will be [tex]160.20rad/sec^2[/tex]

Explanation:

We have given radius of the circle r = 0.685 m

Angular acceleration [tex]\alpha =63.8rad/sec^2[/tex]

Angular speed [tex]\omega =15rad/sec[/tex]

Centripetal acceleration will be

[tex]a_c=\omega ^2r=15^2\times 0.685=154.125rad/sec^2[/tex]

Tangential acceleration will be

[tex]a_t=r\alpha =0.685\times 63.8=43.7rad/sec^2[/tex]

(a) Total acceleration will be equal to

[tex]a=\sqrt{a_t^2+a_c^2}[/tex]

[tex]a=\sqrt{43.7^2+154.125^2}=160.20rad/sec^2[/tex]

So total acceleration will be [tex]160.20rad/sec^2[/tex]

A mass m = 1.1 kg hangs at the end of a vertical spring whose top end is fixed to the ceiling. The spring has spring constant k = 115 N/m and negligible mass. At time t = 0 the mass is released from rest at a distance d = 0.35 m below its equilibrium height and undergoes simple harmonic motion with its position given as a function of time by y(t) = A cos(ωt – φ). The positive y-axis points upward. show answer Correct Answer 17% Part (a) Find the angular frequency of oscillation, in radians per second. ω = 10.22 ✔ Correct! show answer Incorrect Answer 17% Part (b) Determine the value of the coefficient A, in meters.

Answers

Answer:

a) = 10.22 rad/s

b) = 0.35 m

Explanation:

Given

Mass of the particle, m = 1.1 kg

Force constant of the spring, k = 115 N/m

Distance at which the mass is released, d = 0.35 m

According to the differential equation of s Simple Harmonic Motion,

ω² = k / m, where

ω = angular frequency in rad/s

k = force constant in N/m

m = mass in kg

So,

ω² = 115 / 1.1

ω² = 104.55

ω = √104.55

ω = 10.22 rad/s

If y(0) = -0.35 m and we want our A to be positive, then suffice to say,

The value of coefficient A in meters is 0.35 m

How do the electrons in the bulb's filament, far from the battery and its emf, "know" that they should flow?

Answers

Answer:this is obviously because free electrons can easily move in the metal due to potential difference, and they are inserted in the wire from the negative terminal of the battery and pulled away ( come back) from the wire into the battery at positive terminal.

Final answer:

Electrons in a lightbulb filament flow due to the electric fields created by a connected battery, encountering resistance that dissipates energy as heat and allows the bulb to emit light.

Explanation:

Electrons 'know' to flow in a bulb's filament due to the electric fields created when a battery is connected to a circuit. These fields exert a force on the electrons, causing them to move. The flow of electrons is sustained by the potential difference (emf) provided by the battery, but it's not perpetual because as electrons move through the resistive filament, they encounter resistance analogous to friction, which causes energy to be dissipated as heat. This is the principle by which the bulb emits light. An open circuit, like if a wire is cut, prevents the flow of charge, demonstrating the necessity of a closed path for current to flow.

The resistance to electron movement through the filament is due to interactions with the material's atoms, as described by Newton's second law (a = Ftotal/m). This resistance leads to the conversion of electrical energy into heat, which in the case of an incandescent lightbulb, is necessary for it to glow. Without resistance, electrons accelerated by the emf would continue gaining kinetic energy, which does not occur due to this energy transformation. The steady flow of electrons is the result of these resisting forces balancing out the force exerted by the electric field, leading to a constant flow of current as long as the circuit is complete.

A small mirror is attached to a vertical wall, and it hangs a distance of 1.70 m above the floor. The mirror is facing due east, and a ray of sunlight strikes the mirror early in the morning and then again later in the morning. The incident and reflected rays both lie in a plane that is perpendicular to both the wall and the floor. Early in the morning, the ray is observed to strike the floor at a distance of 3.75 m from the base of the wall. Later on in the morning, the ray strikes the floor at a distance of 1.18 m from the wall. The earth rotates at 15.0 degrees per hour. How much time (in hours) has elapsed between the two observations

Answers

Answer:

Around 2 hours

Explanation:

The answer is given in the pictures below. All the page numbers are circled on the top left corner of each page.

Final answer:

The question deals with calculating time based on the change in position of a reflected sunlight ray due to Earth's rotation, with the Earth rotating at a rate of 15 degrees per hour.

Explanation:

The question concerns the reflection of light from a mirror and the calculation of time based on the Earth's rotation rate. The sunlight's path changes throughout the morning due to the Earth's rotation, which moves at a consistent rate of 15 degrees per hour. Given the different positions where the ray of sunlight strikes the floor at different times, we can calculate the angle change and then the time elapsed.

To find the time elapsed, we first determine the angular change between the two observations. The change in position on the floor from 3.75 m to 1.18 m corresponds to a difference in angle when considering the mirror as the vertex of a right triangle with the wall. Next, we apply the Earth's rotational rate to find the corresponding time.

A nearsighted person cannot see objects further away than 10 m clearly. This person wants to be able to see objects 300 m away without trouble. What is the focal length of the lens you would prescribe? (Ignore the distance between the person’s eye and the lens.)

a. 9.7 m
b. – 9.7 m
c. No such lens can be prescribed.
d. 10.3 m
e. – 30 m
f. 30 m
g. – 10.3 m

Answers

Answer:

d.-10.3m

Explanation:

Note for short sightedness the focal length is negative

Let do be object distance=10m

And di= image distance=-300m

Using lens formula

F=do*di/do-di= 10*300/10-300=-10.3m

Answer:

d. 10.3 m

Explanation:

For a nearsighted person,

1/f = (1/v)+(1/u).................... Equation 1

f = focal, v = image distance, u = object distance.

f = vu/(v+u)................. Equation 2

Given: v = -10 m, u = 300 m

Substitute into equation 2

f = (-10×300)/(-10+300)

f = -3000/290

f = -10.34 m

therefore a concave lens of focal length 10.34 m is  required.

The right option is d. 10.3 m

2. An electrical heater 200mm long and 15mm in diameter is inserted into a drilled hole normal to the surface of a large block of material having a thermal conductivity of 5W/m·K. Estimate the temperature reached by the heater when dissipating 25 W with the surface of the block at a temperature of 35 °C.

Answers

Answer:

The final temperature is 50.8degrees celcius

Explanation:

Pls refer to attached handwritten document

Answer: 50.63° C

Explanation:

Given

Length of heater, L = 200 mm = 0.2 m

Diameter of heater, D = 15 mm = 0.015 m

Thermal conductivity, k = 5 W/m.K

Power of the heater, q = 25 W

Temperature of the block, = 35° C

T1 = T2 + (q/kS)

S can be gotten from the relationship

S = 2πL/In(4L/D)

On substituting we have

S = (2 * 3.142 * 0.2) / In (4 * 0.2 / 0.015)

S = 1.2568 / In 53.33

S = 1.2568 / 3.98

S = 0.32 m

Proceeding to substitute into the main equation, we have

T1 = T2 + (q/kS)

T1 = 35 + (25 / 5 * 0.32)

T1 = 35 + (25 / 1.6)

T1 = 35 + 15.625

T1 = 50.63° C

A laser shines on a pair of vertical slits. The horizontal distance L 1 between the laser and the ruler is 12.3 m. The distance L 2 between the laser and the slits is 0.511 m. The distance d is 0.440 mm. A laser is located a distance L subscript 1 from a ruler and a distance L subscript 2 from a barrier containing two, narrow slits. The slit separation is d. An interference intensity pattern is shown at the position of the ruler. The intensity pattern has a central maximum at 0 centimeters. The first dark fringe is at plus or minus 1.6 centimeters. The first bright fringe is at about plus or minus 3 centimeters. The second dark fringe is at about plus or minus 4.8 centimeters. The second bright fringe is at about plus or minus 6.4 centimeters. The third dark fringe is at plus or minus 8 centimeters. The illustration is not to scale. Note that the ruler measures in centimeters. Calculate the wavelength ? of the light.

Answers

Final answer:

To calculate the wavelength of the light, use the equation d sin θ = mλ. Plugging in the values, we find that the wavelength is 563 nm.

Explanation:

In order to calculate the wavelength of the light, we can use the equation d sin θ = mλ, where d is the slit separation, θ is the angle of the bright fringe, m is the order of the fringe, and λ is the wavelength of the light. In this case, we are given the slit separation (0.0100 mm) and the angle of the third bright line (10.95°). We can rearrange the equation to solve for λ:

λ = d sin θ / m

Plugging in the values, we get:

λ = (0.0100 mm) sin(10.95°) / 3

λ = 5.63 x 10-7 mm or 563 nm

) So we are in a Universe with no center and no edge, but it is expanding... and it might be infinite. And it is all space and time and mass and energy, but was born out of nothingness. What do you think about this? Does it seem sensible and natural or do you find it odd and confusing? Can you think of any better explanation for what we see? I would like your answer to be at least five (5) sentences long.

Answers

Final answer:

The multiverse concept along with the universe's infinite nature and lack of a center challenges our understanding, yet represents current scientific explanations supported by observational evidence and theoretical models.

Explanation:

The concept of the multiverse, suggesting that our universe is just one among countless others, is a challenging yet intriguing idea. The nature of cosmic expansion, driven by mass and dark energy, adds complexity to our universe's fate, with models predicting expansion forever or eventual contraction. While it may seem sensible to accept that the Big Bang led to a universe with no center or edge, and infinite potential, it's natural to find this overwhelming due to its departure from human intuition. These concepts push the boundaries of our understanding and stimulate philosophical and metaphysical discussions, demonstrating the dynamic involvement of spacetime. As opinions on what constitutes the 'center' or 'boundary' of an infinite universe vary, the scientific community continues to explore why the universe is structured as it is, why certain constants have their values, and what 'accidents' may have been necessary for existence as we perceive it.

To understand the formula representing a traveling electromagnetic wave.

Light, radiant heat (infrared radiation), X rays, and radio waves are all examples of traveling electromagnetic waves. Electromagnetic waves comprise combinations of electric and magnetic fields that are mutually compatible in the sense that the changes in one generate the other.

The simplest form of a traveling electromagnetic wave is a plane wave. For a wave traveling in the x direction whose electric field is in the y direction, the electric and magnetic fields are given by

E? =E0sin(kx??t)j^,
B? =B0sin(kx??t)k^.

This wave is linearly polarized in the y direction.

1.a. In these formulas, it is useful to understand which variables are parameters that specify the nature of the wave. The variables E0 and B0are the __________ of the electric and magnetic fields.

Choose the best answer to fill in the blank.

1. maxima
2. amplitudes
3. wavelengths
4. velocities

b. The variable ? is called the __________ of the wave.

Choose the best answer to fill in the blank.

1. velocity

2. angular frequency

3. wavelength

c. The variable k is called the __________ of the wave.

Choose the best answer to fill in the blank.

1. wavenumber

2. wavelength

3. velocity

4. frequency

d. What is the mathematical expression for the electric field at the point x=0,y=0,z at time t?

1. E=E0sin(??t)j^

2. E =E0sin(??t)k^

3. E =0

4. E =E0sin(kz??t)i^

5. E =E0sin(kz??t)j^

e. For a given wave, what are the physical variables to which the wave responds?

1. x only

2. t only

3. k only

4. ? only

5. x and t

6. x and k

7. ? and t

8. k and ?

Answers

Answer:

please read the answer below

Explanation:

We have that both electric field and magnetic field are given by:

[tex]\vec{E}=E_osin(kx-\omega t)\hat{j}\\\\\vec{B}=B_osin(kx-\omega t)\hat{k}[/tex]

I complete with bold words the answers:

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

a. In these formulas, it is useful to understand which variables are parameters that specify the nature of the wave. The variables E0 and B0are the magnitudes of the electric and magnetic fields.

2. amplitudes

b. The variable w is called the angular frequency of the wave.

2. angular frequency

c. The variable k is called the wavenumber of the wave.

1. wavenumber

c.

1. E =E0sin(wt)k^

d.

6. x and t

hope this helps!!

The neurons of giant squids, for example, consist of axons with very large radii, which allows the squid to react very quickly when confronted with a predator. Assuming no change in the resistivities or membrane thickness of the axon, by what factor must the radius of the axon increase such that the speed of the pulse increases by a factor of 10

Answers

Answer:

100

Explanation:

[tex]\rho_m[/tex] = Resistivity of axon

r = Radius of axon

t = Thickness of the membrane

[tex]\rho_a[/tex] = Resistivity of the axoplasm

Speed of pulse is given by

[tex]v=\sqrt{\dfrac{\rho_mrt}{2\rho_a}}[/tex]

So, radius is given by

[tex]r=\dfrac{2\rho_a}{\rho_mt}v^2[/tex]

If radius is increased by a factor of 10 new radius will be

[tex]r_2=\dfrac{2\rho_a}{\rho_mt}(10v)^2\\\Rightarrow r_2=100\dfrac{2\rho_a}{\rho_mt}v^2\\\Rightarrow r_2=100r[/tex]

So, The radius will increase by a factor of 100.

One possible explanation for a galaxy's type invokes the angular momentum of the protogalactic cloud from which it formed. Suppose a galaxy forms from a protogalactic cloud with a lot of angular momentum. Assuming its type has not changed as a result of other interactions, we'd expect this galaxy to be ______.

Answers

Answer:

A spiral galaxy

Explanation:

If the bore of an engine is increased without any other changes except for the change to proper-size replacement pistons. the displacement will ________ and the compression rate will ________.

Answers

Answer:

increase, increase

Explanation:

If the bore of an engine is increased without any other changes except for the change to proper-size replacement pistons. the displacement will increase and the compression rate will increase.

Further Explanation:

If the bore is increased, there are several benefits to this. There is more area for the valves this improves flow through the engine. The compression ratio will increase, thereby increasing thermal efficiency. The displacement also increases as the power output increase. Also, higher RPM will further increase power.

However, a decrease in bore will result in corresponding reduction in displacement and power output.

A proton is accelerated from rest through a potential difference of 2.5 kV and then moves perpendicularly through a uniform 0.60-T magnetic field. What is the radius of the resulting path

Answers

Answer:

1.2cm

Explanation:

V=(2ev/m)^1/2

=(2*1.6*10^19 x2500/ 1.67*10^27)^1/2

=6.2x10^5m/s

Radius of resulting path= MV/qB

= 1.67*10^-27x6.92*10^6/1.6*10^-16 x0.6

=0.012m

=1.2cm

Answer:

0.012m

Explanation:

To find the radius of the path you can use the formula for the radius od the trajectory of a charge that moves in a constant magnetic field:

[tex]r=\frac{mv}{qB}[/tex]

m: mass of the proton 9.1*10^{-31}kg

q: charge of the proton 1.6*10^{-19}C

B: magnitude of the magnetic field 0.60T

v: velocity of the proton

In order to use the formula you need to calculate the velocity of the proton. This can be made by using the potential difference and charge, that equals the kinetic energy of the proton:

[tex]qV=E_k=\frac{1}{2}mv^2\\\\v=\sqrt{\frac{2qV}{m}}=\sqrt{\frac{2(1.6*10^{-19}C)(2.5*10^{3}V)}{1.67*10^{-27}kg}}=6.92*10^{5}\frac{m}{s}[/tex]

Then, by replacing in the formula for the radius you obtain:

[tex]r=\frac{(1.67*10^{-27}kg)(6.92*10^5\frac{m}{s})}{(1.6*10^{-19}C)(0.60T)}=0.012m[/tex]

hence, the radius is 0.012m

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