A 4.33 kg cat has 41.7 J of KE How fast is the cat moving?

Answer:

c)7 mph

Explanation:

Going downstream the speed of the boat is added to the speed of the water, on the way back it is opposite to it, then the speed of the water is substracted to that of the boat, and we have the total time of the trip, then we can write down a system of equations as follows:

x:=Speed of water that is being asked

t1:= time going downstream

t2:= time going upstream

(21+x)*t1=14  (1)

(21-x)*t2=14  (2)

t1+t2=1.5       (3)

then t1=1.5-t2, replacing this in (1) we have  (21+x)*(1.5-t2)=14, then t2=1.5-(14/(21+x))  (4). Doing the same in (2) we get t2=14/(21-x)  (5), this way we can use (4) and (5) and get that:

1.5-(14/(21+x))=14/(21-x), doing the operations we get that 588/(441-x^2)=1.5 or equivalently 1.5x^2-73.5=0 or x^2-49=0 or (x-7)(x+7)=0, then the possible answers are x=7 or x= -7, here we consider the positive answer, that in magnitude is the same as the other, because we already considered the direction of the water into the equations. Then the answer is c) 7mph.

Final answer:

The speed of the current is 3 miles per hour, obtained by setting up an equation based on the total time taken for an upstream and downstream trip and solving for the current's speed. So the correct option is a.

Explanation:

To find the speed of the current, we can set up an equation considering the speed of the boat in still water (which we know is 21 miles per hour) and the speed of the current, which we will call 'c'.

When the boat goes upstream, the effective speed is reduced by the speed of the current, so it's 21 - c miles per hour. Similarly, when the boat goes downstream, the effective speed is increased by the speed of the current, making it 21 + c miles per hour.

Let's calculate the time taken to travel upstream and downstream using the distance and the effective speed. For upstream, it is 14 / (21 - c) hours, and for downstream, it is 14 / (21 + c) hours. The total time for the trip is given as 1.5 hours, so we sum the upstream and downstream times to set up the equation:

14 / (21 - c) + 14 / (21 + c) = 1.5

By solving this equation for 'c', we find that the speed of the current is 3 miles per hour, which corresponds to option (a).

Answer:

10 m/s

Explanation:

u = 20 m/s

v = 0 m/s

t = 5.8 s

Let a be the acceleration and s be the distance traveled by the car in time t.

use first equation of motion

v = u + a t

0 = 20 + a x 5.8

a = -3.45 m/s^2

Use third equation of motion

[tex]v^{2}=u^{2}+2as[/tex]

[tex]0^{2}=20^{2}-2 \times3.45 \times s[/tex]

s = 58 m

The average speed is defined as the ratio of distance traveled to the time taken.

[tex]Average speed = \frac{58}{5.8} = 10 m/s[/tex]

thus, the average speed of the car is 10 m/s.  

Answer:

Motion Parallax

Explanation:

According to my research on different scientific anomalies or terminology, I can say that based on the information provided within the question this is an example of Motion Parallax. This term refers to a depth cue where an individual views objects that are closer to us as moving faster than those objects further from us. Which is what the companion in this situation is describing.

I hope this answered your question. If you have any more questions feel free to ask away at Brainly.

Answer:

The answer to your question is: 1.19 gr/ml

Explanation:

empty flask weighs = 45.4 g

filled with water = 121.8 g

filled with a different substance = 91.39 g

density of the second liquid =

First we must calculate the mass of water in the flask by subtracting the flask filled with water and the flask empty.

mass =  flask filled with water - the flask empty.

mass = 121.8 - 45.4 gr

mass = 76.4 gr

The density of water is always 1 gr/ml

and density is mass/volume

from here we calculate the volume = mass/density

                                             volume = 76.4/1 = 76.4 ml

Now we calculate the density of the other liquid

           density = 91.39/76.4 = 1.19 g/ml

Explanation:

If I assume you are talking about on Earth, then by using the equation

Weight Force=mg

382=(10)m

m=382/10

m=38.2 kg

Note that regardless of whether you are on Earth or any other planet or body the mass of something does not change. Only the weight of it changes as the gravitational acceleration (g) varies from planet to planet.

Answer : The mass of a dog that weighs 382 N is, 38.93 kg

Explanation :

Formula used :

[tex]F=m\times g[/tex]

where,

F = force = 382 N

m = mass of a dog = ?

g = acceleration due to gravity = [tex]9.8m/s^2[/tex]

Now put all the given values in the above formula, we get:

[tex]382N=m\times 9.8m/s^2[/tex]

[tex]382\frac{kg.m}{s^2}=m\times 9.8m/s^2[/tex]

[tex]m=38.98kg[/tex]

Thus, the mass of a dog that weighs 382 N is, 38.93 kg

Answer:

11 kg of gas are emmited to the atmosphere

Explanation:

The problem consists in calculating the total mass of the gases produced in the combustion reaction of the carcoal.

In this case we consider the simple combustion reaction:

C+O2 -> CO2

In relation 1:1 molar with the oxygen.

In this case, the limitant reactant is the carbon, so we make the calculations based in the 3kg of carbon combusted.

First we convert the mass of carbon into mol of carbon

m,C=3kg=3000 g of C

Then we have the mol

n,C=3000g/(12 g/mol)=249.77 mol C

This number also corresponds to the number of oxygen mol reacting with the charcoal. Therefore we calculate the mass of oxygen.

m,O2=249.77 mol *(32 g/mol) = 7990 g =7.99 kg, aproximately 8 kg

Then the total mass of gas is the mass of charcoal plus the mass of oxygen

m,total=3kg + 8kg=11kg

Answer:

The engine would be warm to touch, and the exhaust gases would be at ambient temperature. The engine would not vibrate nor make any noise. None of the fuel entering the engine would go unused.

Explanation:

In this ideal engine, none of these events would happen due to the nature of the efficiency.

We can define efficiency as the ratio between the used energy and the potential generable energy in the fuel.

n=W, total/(E, available).

However, in real engines the energy generated in the combustion of the fuel transforms into heat (which heates the exhost gases, and the engine therefore transfering some of this heat to the environment). Also, there are some mechanical energy loss due to vibrations and sound, which are also energy that comes from the fuel combustion.

Final answer:

This answer addresses the implications of a hypothetical 100%-efficient engine in an automobile, discussing its heat production, exhaust impact, noise and vibration levels, and fuel usage.

Explanation:

If an automobile had a 100%-efficient engine:

Answer:

2.1 s

Explanation:

The motion of the ball is a projectile motion. We know that the horizontal range of the ball is

[tex]d = 50 m[/tex]

And that the initial speed of the ball is

[tex]u=25 m/s[/tex]

at an angle of

[tex]\theta=20^{\circ}[/tex]

So, the horizontal speed of the ball (which is constant during the entire motion) is

[tex]u_x = u cos \theta = 25 \cdot cos 20^{\circ} = 23.5 m/s[/tex]

And since the horizontal range is 50 m, the time taken for the ball to cover this distance was

[tex]t=\frac{d}{u_x}=\frac{50}{23.5}=2.1 s[/tex]

which is the time the ball spent in air.

Answer:

Explanation:

(a)

Gold has an atomic mass of 197 g/mol means 197 g of gold contains 6.023×10^{-23} atoms.

therefore number of atoms in 17.4 g is

[tex]n= \frac{6.23\times10^{23}\times17.4}{197}[/tex]

[tex]5.32\times10^{22}[/tex]

Number of protons in each atom is 79.

therefore Total number of protons is 5.32×10^{22}×79 =4.2×10^24. protons

Their total positive charge is 4.2×10^{24}×1.6×10^{-19) =6.72×10^5 C.

(b)

equal number of protons should be there to neutralize the material therefore number of electrons is 4.2×10^(24.)

Answer:

the reason for the acceleration month that the coefficient of kinetic friction is less than the coefficient of satic frictionExplanation:

This exercise uses Newton's second law with the condition that the acceleration is zero, by the time the body begins to slide. At this point the balance of forces is

    fr- w || = 0

The expression for friction force is that it is proportional to the coefficient of friction by normal.

    fr = μ N

When the system is immobile, the coefficient of friction is called static coefficient and has a value, this is due to the union between  the surface, when the movement begins some joints are broken giving rise to coefficient of kinetic friction less than static.  

In consequence a lower friction force, which is why the system comes out of balance and begins to accelerate.

      μ kinetic <μ static

  In all this movement the normal with changed that the angle of the table remains fixed.

Consequently, the reason for the acceleration month that the coefficient of kinetic friction is less than the coefficient of satic friction

To find the electric field at a point directly above the midpoint of the plastic wire, use the formula for the electric field due to a charged line. When the wire is bent into a circle, the electric field at a point directly above its center is zero.

To find the electric field at a point directly above the midpoint of the plastic wire, you can use the formula for the electric field due to a charged line. The formula is given by E = (k * λ) / r, where E is the electric field, k is the Coulomb's constant (9 * 10^9 Nm²/C²), λ is the charge density, and r is the distance from the wire.

In this case, the charge density is 100nC/m and the distance is 6.0cm. Plug in the values to calculate the electric field. Since the wire is nonconducting, it does not affect the direction of the electric field, so the magnitude is the only value you need to find.

(b) When the wire is bent into a circle lying flat on the table, the electric field at a point directly above its center is zero. This is because the electric field due to each small segment of the wire cancels out by the symmetry of the circular shape.

Answer:

[tex]\frac{dA}{dt} = 188.5 m^2/s[/tex]

Explanation:

As we know that area of the circle at any instant of time is given as

[tex]A = \pi r^2[/tex]

now in order to find the rate of change in area we will have

[tex]\frac{dA}{dt} = 2\pi r\frac{dr}{dt}[/tex]

here we know that

rate of change of radius is given as

[tex]\frac{dr}{dt}= 1 m/s[/tex]

radius of the circle is given as

[tex]r = 30 m[/tex]

now we have

[tex]\frac{dA}{dt} = 2\pi (30)(1)[/tex]

[tex]\frac{dA}{dt} = 60\pi[/tex]

[tex]\frac{dA}{dt} = 188.5 m^2/s[/tex]

Answer:

Option b and c

Explanation:

Quantized values are discrete in nature and are not continuous.

These values can be expressed as integral multiples or integers.

Therefore,

Answer:

They are the same (assuming there is no air friction)

Explanation:

Take a look at the picture.

When the first ball (the one thrown upward) gets to the point marked as A, the speed will has the exact same value V but the velocity will now point downward (just like the second ball).

So if you think about it, the first ball, from point A to the ground, will behave exactly like the second ball (same initial speed, same height).

That is why the speeds will be the same when they reach the ground.

Answer:

Velocity is same

Explanation:

Case I:

When the ball throws upwards

Let the velocity of the ball as it hits the ground is V'.

Initial velocity, u = V

Final velocity, v = V'

height = h

acceleration due to gravity = g

Use third equation of motion

[tex]v^{2}=u^{2}+2as[/tex]

By substituting the values

[tex]V'^{2}=V^{2}+2(-g)(-h)[/tex]

[tex]V'=\sqrt{V^{2}+2gh}[/tex]      .... (1)

Case II:

When the ball throws downwards

Let the velocity of the ball as it hits the ground is V''.

Initial velocity, u = V

Final velocity, v = V''

height = h

acceleration due to gravity = g

Use third equation of motion

[tex]v^{2}=u^{2}+2as[/tex]

By substituting the values

[tex]V''^{2}=V^{2}+2(-g)(-h)[/tex]

[tex]V''=\sqrt{V^{2}+2gh}[/tex]      .... (2)

By comparing the equation (1) and equation (2), we get

V' = V''

Thus, the velocity of balls in both the cases is same as they strikes the ground.

Answer:

The mole fraction of hexane is 0.67

Explanation:

This problem can be solved using Dalton´s law and Raoult´s law.

The vapor pressure of a mixture of gases is the sum of the partial pressures of  each gas (Dalton´s law).

Example:

In a mixture of gases A and B

Pt = PA + PB

where:

Pt = total pressure

PA = partial pressure of A

PB = partial pressure of B

In an ideal solution, the vapor pressure of each component is equal to the vapor pressure of the pure component times the mole fraction of the component in the solution (Raoult´s law).

Example:

In a solution containing A and B, the vapor pressure of A in the solution will be:

PA = P(pure A) * Xa

Where

PA = vapor pressure of A in the solution

P(pure A) = vapor pressure of pure A

Xa = mole fraction of A

In our problem, we have that the vapor pressure of the solution is 241 torr.

Then, using Dalton´s law:

Pt = P(hexane) + P(Pentane)

Using Raoult´s law:

P(hexane) = P(pure hexane) * X(hexane)

P(pentane) = P(pure pentane) * X(pentane)

We also know that the sum of the molar fractions of each component in a solution equals 1:

X(hexane) + X(pentane) = 1

X(pentane) = 1 - X(hexane)

Replacing in the Dalton´s law in terms of X(hexane):

Pt = P(pure hexane) * X(hexane) + P(pure pentane) * (1 - X(hexane))

Solving for X(hexane):

Pt = P(pure hex) * X(hex) + P(pure pent) - P(pure pent) * X(hex)

Replacing with the data:

241 torr = 151 torr * X(hex) + 425 torr - 425 torr*X(hex)

-184 torr = -274 torr * X(hex)

-184torr/-274 torr = X(hex)

X(hex) = 0.67

The mole fraction of hexane in the solution is 1.59.

To find the mole fraction of hexane in the solution, we can use Raoult's law, which states that the partial pressure of a component in a solution is equal to the product of the mole fraction of that component and its vapor pressure.

Let's calculate the mole fraction of hexane:

Partial pressure of hexane = mole fraction of hexane * vapor pressure of hexane

241 torr = x * 151 torr

241 torr / 151 torr = x = 1.59

The mole fraction of hexane in the solution is 1.59.

Answer:

The acceleration is given by de second derivative of x(t) which is equal to [tex]\frac{d^f{2}f(x) }{d^{2}x }=12at^{2} + 6bt[/tex] m/s^2

Explanation:

a) We have the equation x(t)=at^4+bt^3+ct which is the position of the body of mass m at a time t

Where a, b and c are constants

From the rules of differenciation we have that the first derivative of the position is the velocity  and the second derivative is the acceleration.

Hence the first derivative of the function is equal to [tex]4at^{3} +3bt^{2}+c[/tex][/tex] m/s

Don´t forget to write down the unities

Then we have to derivate again this equation, so we have

[tex][tex]\frac{d^{2}f(x) }{d^{2}x }=12at^{2} + 6bt[/tex] m/s^2[/tex]

b) Remembering the Newton´s laws we know that

[tex]F=ma[/tex]

where:

F is the force

m is the mass

and a is the acceleration

From the first part we know the value of the acceleration which is

[tex]\frac{d^{2}f(x) }{d^{2}x }=12at^{2} + 6bt[/tex] m/s^2

So using the second law formula and replacing the values we have that

F=m([tex]\frac{d^{2}f(x) }{d^{2}x }=12at^{2} + 6bt[/tex] ) N

Remember the that N= Newton which is kg*m/s^2

Answer:3.95 m/s

Explanation:

Given

Initial velocity(u)[tex]=20.1 m/s[/tex]

launch angle[tex]=47.8^{\circ}[/tex]

Player is 53 m away

Range of projectile

[tex]R=\frac{u^2sin2\theta }{g}[/tex]

[tex]R=\frac{20.1^2\times sin95.6}{9.8}[/tex]

R=41.02 m

so he need to run 53-41.02=11.98 m

Time of flight of projectile [tex]=\frac{2usin\theta }{g}[/tex]

T=3.03 s

thus average speed of boy [tex]s_{avg}=\frac{11.98}{3.03}=3.95 m/s[/tex]

Answer:

Assuming the divers are not moving. The diving partner is at 1600 feet.

Explanation:

The sound wave have to  go to the diving partner and return, so its traveling the double of the total distance.

Been X= distance, V= speed, and t= time

[tex]x=v*t\\[/tex]

[tex]WaveTravelDistance=4000*0.8\\\\Distance to the partner=WaveTravelDistance/2\\\\WaveTravelDistance=3200feet\\\\Distance to the partner=1600feet[/tex]

Answer:

Explanation:

Since it only mentions the height we only have to concern ourselves with the y direction, up and down, so that's nice.  Also, acceleration due to gravity is -9.8 m/s^2

First we want the formula for the position of the object, for that we need the initial speed.  We have an initial speed but we need the speed in the y direction.  To do that we break the speed we have into its x and y components.  Imagine a right triangle where the hypotenuse is 100 and the angle between that and the horizontal leg is 42.8 degrees.  Notice that the legs of the right triangle are vertical and horizontal, they represent the y and x components of the speed respectively.  Anyway, we want the y component, so the vertical.  Relative to the given angle  that is the "opposite" side, when we use SOH CAH TOA.  Let me know if this doesn't make sense and I can draw it out.

Now, using trig, we can find the y component  with SOH.  so sin(42.8)=y/100.  Make sure your calculator is in degree mode of course.  we get

y = 100*sin(42.8) = 67.94 so the vertical speed is 67.94 m/s.

With that now we can use the displacement formula s = vi*t + .5a*t^2 if you don't remember this formula you definitely should have some kind of paper or something with all your physics formula.  Anyway, we can plug in all values except for t, which is our variable.

s = 95.5

vi=67.94

a= -9.8

95.5 = 67.94t + .5(-9.8)t^2

Then if you subtract 95.5 from both sides you have a traditional quadratic equation you can solve with the quadratic formula, or completing the square or however you solve them.  If you need help with this step let me know, or if something else didn't make sense.  

Answer:

[tex]v_f=8.4m/s[/tex]    

Explanation:

We need to use the conservation of momentum Law, the total momentum is the same before and after the kid leaves the skate.

In the axis X:

[tex](m_{kid}+m_{skate})*v_{o}=m_{kid}*v_f[/tex]     (1)

[tex]v_f=(m_{kid}+m_{skate})*v_{o}/m_{kid}=(44+2.2)*8/44=8.4m/s[/tex]  

Answer:

The International Astronomical Union (IAU)  has accepted 88 constellations in the sky.

Explanation:

Constellations has been used since the beginnings of civilizations and each one of them named them as they considered appropiate. It means Greeks' constellations were different than the ones described by Chinese, so it was necessary to gather all these constellations and make a great record with all of them, but there was a problem: Some constellations from different civilizations overlaped because they shared the same stars. There was necessary to put some order on this and that is when in 1922 the International Astronomical Union (IAU) defned a set of 88 moderm constellations  that would become the international standard to look at the night sky. Each one of them is unique and does not share stars with the other constellations.  

Answer:

25 Ampers

Explanation:

As the current in a defibrillation is DC (Direct current), we can use simply the Ohm's law which shows:

V=I*R

Then if we want to know the current, we can follow the next step for I:

I=V/R

Using the information, and asumming electrode contact area is large and conducting gel is used on the skin (as is normal) , we can solve:

Imax=Vmax/R

Imax= 500 V / 20 ohms

Imax= 25 Ampers

*Fact: The time in this case doesn't make any difference in the result.

Answer:

B

Explanation:

In a common rail system, the fuel is distributed to the injectors from the rail where there is high pressure accumulation.High pressure fuel pump feds the rail and with the help of the start and end signals the injector is activated.For example in diesel common rail direct injection systems, the rail is connected to injectors using individual pipes in that the injectors work hand in hand with the fuel pump which ensures fuel injection timing and amount. Comparing this with early models, the fuel pump was responsible for timing, quantity and pressure.So power stroke in a modern common rail system does not only rely on single injection of pump but also has multiple injection events during combution process.

Answer:

Explanation:

When a parachutist jump from an aeroplane, there are two forces acting on the parachutist.

One is the force called gravitational force which is acting downwards.

Other is the force of air resistance which is acting upwards.

When the parachute is not opened, the gravitational force is more than the air resistance force due to which the parachutist experiences a force with which he is coming down and thus , there is an acceleration in the body and the velocity of the body goes on increasing.

When the parachute is opened, the gravitational force is balanced by the air resistance force due to which there is no net force acting on the body of parachutist and thus, he comes down with uniform velocity as acceleration in the body is zero.

In this condition, the magnitude of gravitational force is equal to the air resistance force.

Answer:

K = 1.72 *10^{-11} N/m

Explanation:

given data:

L= 2.14*10^{-6} m

[tex]\Delta = 1.4%* of L[/tex]

           [tex]= \frac{1.4}{100} *2.14*10^{-6}[/tex]

           = 2.99*10^{-8} m

[tex]L' = L - \Delta L[/tex]

[tex]L ' = 2.14*10^{-6} -2.99*10^{-8}[/tex]

[tex]L = 2.11*10^{-6} m[/tex]

electrostatic force = spring force

[tex]\frac{ kq^2}{L'^2} = K \Delta L[/tex]

putting all equation to get spring constant K value

[tex]\frac{8.98*10^9 *1.6*10^{-19}}{2.11*10^{-6}} = K 2.99*10^{-8}[/tex]

K = 1.72 *10^{-11} N/m

Answer:

α=1.013rev/min^2

Explanation:

Wo=initial angular speed=158rev/min

t=time=2.6h=156min

Wf=final angular speed=0rev /min  , this happens because in the end the wheel stops

this is a circular motion with uniform acceleration therefore we can use the following equation

α=angular aceleration=(Wf-Wo)/t

α=(0-158)/156=1.013rev/min^2

Answer:

B.magnitude and direction

Explanation:

Vector is moved from one place to another.

Example: acceleration

only scalar have magnitude only

Example: speed , temperature

The correct answer is B. Magnitude and direction

Explanation:

In physics, vectors are used to represent motion, forces acting on a body, among other common concepts. A vector is usually represented as a line that connects to different points and has a specific direction. Due to this, all vectors have a magnitude (specific size or length representing a concept) and a direction (position of forces, movements, etc). For example, in physics, it is common to use vectors to represent the forces that act on a body such as gravity or friction and each of these ave specific magnitudes represented with the length of the vector and specific directions depending on the position of the vector. Thus, vectors have both magnitude and direction.

Answer:

46 meters

Explanation:

In the figure you can see law of cosines.

In your case

α = 22.5° + 42 ° = 64.5 °

b = 15 m (distance between your's tent and Joe's tent)

c = 42 m (distance between your's tent and Karl's tent)

a is the distance between Joe's tent and Karl's tent

Replacing in the first equation:

[tex]a^2 = 15^2 m^2 + 42^2 m^2 - 2 \times 15 \times 42 \times cos(64.5) [/tex]

[tex] a = \sqrt{2111.46 m^2} [/tex]

[tex] a = 46 m [/tex]

The hypothesis could be stated as follows: "Since there is no direct sunlight at night, the temperature of the air blown by the bedroom air conditioner is colder at night than it is during the day."

You may devise an experiment to gauge the temperature of the air being blasted by the air conditioner both at night and during the day in order to verify this theory. This is a general description of the experiment.

Place a thermometer or temperature sensor close to the air conditioner's outlet, which is where the room's cool air is blown. Make sure the sensor is in the same spot for the measurements during the day and at night.

The exact relationship between the air temperature blasted by the air conditioner and the presence or absence of direct sunshine is what the experiment attempts to investigate. According to the theory, cooler air may be blasted by the air conditioner during the daytime when there is sunlight but warmer air during the night when there is no direct sunlight.

Hence, the hypothesis could be stated as follows: "Since there is no direct sunlight at night, the temperature of the air blown by the bedroom air conditioner is colder at night than it is during the day."

To learn more about the hypothesis, here:

https://brainly.com/question/35154833

#SPJ12

Final answer:

The average angular velocity of the cylinder is calculated using the relationship between linear velocity and radius, with the formula ω = v / r. With a final linear velocity of 7.38 m/s and a radius of 5.08 cm, the average angular velocity is about 145.27 rad/s.

Explanation:

To calculate the average angular velocity of the cylinder, we must first understand the relationship between linear velocity and angular velocity. Angular velocity (ω) is related to linear velocity (v) through the radius of the object according to the equation ω = v / r, where r is the radius of the cylinder. Given that the final linear velocity is 7.38 m/s and the radius is 5.08 cm (or 0.0508 meters), we can calculate the average angular velocity.

Calculating the average angular velocity:

Therefore, the average angular velocity of the cylinder is approximately 145.27 rad/s.