Answers
The term mechanical advantage is used to described how effectively a simple machine works. Mechanical advantage is defined as the resistance force moved divided by the effort force used. In the lever example above, for example, a person pushing with a force of 30 lb (13.5 kg) was able to move an object that weighed 180 lb (81 kg). So the mechanical advantage of the lever in that example was 180 lb divided by 30 lb, or 6. The mechanical advantage described here is really the theoretical mechanical advantage of a machine. In actual practice, the mechanical advantage is always less than what a person might calculate. The main reason for this difference is resistance. When a person does work with a machine, there is always some resistance to that work. For example, you can calculate the theoretical mechanical advantage of a screw (a kind of simple machine) that is being forced into a piece of wood by a screwdriver. The actual mechanical advantage is much less than what is calculated because friction must be overcome in driving the screw into the wood.
Sometimes the mechanical advantage of a machine is less than one. That is, a person has to put in more force than the machine can move. Class three levers are examples of such machines. A person exerts more force on a class three lever than the lever can move. The purpose of a class three lever, therefore, is not to magnify the amount of force that can be moved, but to magnify the distance the force is being moved. As an example of this kind of lever, imagine a person who is fishing with a long fishing rod. The person will exert a much larger force to take a fish out of the water than the fish itself weighs. The advantage of the fishing pole, however, is that it moves the fish a large distance, from the water to the boat or the shore.
Related Questions
A ball is thrown at an angle of 45° to the ground. if the ball lands 87 m away, what was the initial speed of the ball? (round your answer to the nearest whole number. use g â 9.8 m/s2.)
Answers
A water bed weighs 1025 N, and is 1.5 m wide by 2.5 m long. How much pressure does the water bed exert if the entire lower surface of the bed makes contact with the floor?
a.
3.6 x 10^2 Pa
b.
2.7 x 10^4 Pa
c.
1.2 x 10^3 Pa
d.
2.7 x 10^2 Pa
Answers
[tex]P = F / A [/tex]
Where,
F: Force
A: area
For the area we have:
[tex]A = (w) * (l) [/tex]
Where,
w: width
l: long
Substituting values we have:
[tex]A = (1.5) * (2.5) A = 3.75 m ^ 2[/tex]
Substituting the values we have:
[tex]P = 1025 / 3.75 P = 273.3333333 N / m ^ 2[/tex]
Rewriting we have:
[tex]P = 2.7 * 10 ^ 2 Pa [/tex]
Answer:
d.
2.7 x 10 ^ 2 Pa
D) 2.7 * 10² Pa
Explanation:
To answer this question, we will use the following equation:
pressure = [tex] \frac{force}{area} [/tex]
1- getting the area:
The water bed is in the form of a rectangle. Therefore, the area can be calculated as follows:
area = length * width
We are given that:
lenth = 2.5 m
width = 1.5 m
This means that:
area = 2.5 * 1.5 = 3.75 m²
2- getting the pressure:
We noted that:
pressure = [tex] \frac{force}{area} [/tex]
We have the force = 1025 N
We calculated the area = 3.75 m²
Substitute in the above equation to get the pressure as follows:
pressure = [tex] \frac{1025}{3.75} [/tex]
pressure = 2.7 * 10² Pa
Hope this helps :)
A proton moves perpendicularly to a uniform magnetic field b with a speed of 3.7 × 107 m/s and experiences an acceleration of 5 × 1013 m/s 2 in the positive x direction when its velocity is in the positive z direction. the mass of a proton is 1.673 × 10−27 kg. find the magnitude of the field. answer in units of t.
Answers
[tex]F=qvB \sin \theta[/tex]
where q is the proton charge, v its velocity, B the magnitude of the magnetic field and [tex]\theta[/tex] the angle between the direction of v and B. Since the proton moves perpendicularly to the magnetic field, this angle is 90 degrees, so [tex]\sin \theta=1[/tex] and we can ignore it in the formula.
For Netwon's second law, the force is also equal to the proton mass times its acceleration:
[tex]F=ma[/tex]
So we have
[tex]ma=qvB[/tex]
from which we can find the magnitude of the field:
[tex]B= \frac{ma}{qv}= \frac{(1.67 \cdot 10^{-27}kg)(5\cdot 10^{13}m/s^2)}{(1-6 \cdot 10^{-19}C)(3.7 \cdot 10^7 m/s)}=0.014 T [/tex]
describe the difference between mechanical and electromagnetic waves. Give an example of each kind of wave related to telecommunications.
Answers
Examples of telecommunication via mechanical waves are sound waves (so, two people speaking to each other, for instance), while examples of telecommunication via electromagnetic waves are the radio waves that transmit the TV signals to the houses.
A man drags a 12.0 kg bag of mulch at a constant speed applying a 39.5 N force at 41°. What is the normal force acting on the bag?
Answers
We need to calculate the force pushing the bag down in order to calculate normal force.
The force that pushes the bag down is equal to:
[tex]F_d=mg-sin(41)\cdot F[/tex]
Where F is the force of a man dragging the bag and mg is gravity pulling the bag down.
The resulting force is:
[tex]F_d=12\cdot9.81-sin(41)\cdot 39.5=91.8N[/tex]
Normal force has the same intensity but the opposite direction of this force.
Based on what you have read, explain the advantages of digital signals over analog signals.
Answers
Sample Response: Digital signals do not pass noise along, so the sound heard is likely very close to the signal that was sent. Digital signals also can be stored more easily than analog signals. Recorded analog signals degrade over time, while recorded digital signals do not.
A sinusoidal wave travels with speed 250 m/s . its wavelength is 3.5 m . part a what is its frequency
Answers
[tex]v=\lambda f[/tex]
The wave of our exercise has a speed of [tex]v=250 m/s[/tex] and a wavelength of [tex]\lambda=3.5 m[/tex], so re-arranging the previous equation we can find its frequency:
[tex]f = \frac{v}{\lambda}= \frac{250 m/s}{3.5 m}=71.4 Hz [/tex]
What mass of electrons would be required to just neutralize the charge of 4.8 g of protons?
Answers
Each proton has a charge of [tex]q=1.6 \cdot 10^{-19} C[/tex], and a mass of [tex]m_p = 1.67 \cdot 10^{-27}kg[/tex]. So, the number of protons is
[tex]N_p = \frac{M}{m_p}= \frac{0.0048 kg}{1.67 \cdot 10^{-27}kg}=2.87 \cdot 10^{24}[/tex] And so the total charge of these protons is [tex]Q_p = qN_p = (1.6 \cdot 10^{-19}C)(2.87 \cdot 10^{24})=4.6\cdot 10^5 C[/tex]
So, the neutralize this charge, we must have [tex]N_e[/tex] electrons such that their total charge is
[tex]Q_e = -4.6 \cdot 10^5 C[/tex]
Since the charge of each electron is [tex]q_e = -1.6 \cdot 10^{-19}C[/tex], the number of electrons needed is
[tex]N_e = \frac{Q_e}{q}= \frac{-4.6 \cdot 10^5 C}{-1.6 \cdot 10^{-19}C}=2.87 \cdot 10^{24} [/tex]
which is the same as the number of protons (because proton and electron have same charge magnitude). Since the mass of a single electron is [tex]m_e=9.1 \cdot 10^{-31}kg[/tex], the total mass of electrons should be
[tex]M_e = N_e m_e = (2.87 \cdot 10^{24})(9.1 \cdot 10^{-31}kg)=2.6 \cdot 10^{-6}kg[/tex]
When populations of two species work together to obtain resources, they are
Answers
Answer:
cooperating.
Explanation:
:)
Does someone have this??
Answers
Let's now answer number 1:
Momentum is mass x velocity
p = mv
Block 1 is 10.00kg and is moving at a speed of 4.50m/s. Just put in what you know to get the answer:
p= 10.00kg x 4.50 m/s = 45 kg.m/s
The momentum of block 1 is 45 kg.m/s.
2. In a collision if one object bumps into another object and they both travel the same direction, the scenario would be considered as a PERFECT inelastic collision.
We can solve for unknowns using this formula:
[tex]m_{1}v_{1i}+m_{2}v_{2i} = (m_{1}+m_{2})v_{f}[/tex]
Where:
m1 = mass of object 1
m2 = mass of object 2
v1i = velocity of object 1 before collision
v2i = velocity of object 2 before collision
So before we solve for what you need, let's list down what you know based on the problem.
m1 = 10.00kg (Block1)
m2 = 25.0kg (Block2)
v1i = 4.50 m /s (Block1)
v2i = 0 m/s (Block2)
You may be wondering why the velocity of object 2 is 0m/s. Well, the problem says that Block 2 was initially at rest, then that means it is not moving, so it's speed would be 0 m/s.
Now use the formula and put in what you know and derive what you do not know.
[tex]m_{1}v_{1i}+m_{2}v_{2i} = (m_{1}+m_{2})v_{f}[/tex]
[tex](10.00kg)(4.50m/s)+(25.0kg)(0m/s) = (10.00kg + 25.00kg)v_{f}[/tex]
[tex](45kg.m/s)+(0) = (35kg)v_{f}[/tex]
[tex](45kg.m/s)= (35kg)v_{f}[/tex]
[tex] \frac{45kg.m/s}{35kg} = v_{f} [/tex]
[tex]1.29m/s = v_{f}[/tex]
Final velocity or vf of both blocks after collision is 1.29m/s.
3. To get the momentum after collision,just keep in mind that momentum is conserved even after collision. So your answer would be 45kg.m/s. If it is necessary for you to solve for it, just solve for it using the equation on the right side, which is (m1+m2)vf.
(m1+m2)vf
=(10.00kg+25.0kg)(1.29m/s)
=(35kg)(1.29m/s)
=45.15kg.m/s or 45 kg.m/s
As for the next problem, a cannon being fired is also considered a collision and this type of collision is called explosion, where the momentum before and after collision is zero. Why? Because before firing, the ball is not moving and neither is the cannon.
So now that we know this, using the formula of explosion we can solve for what we need.
[tex]m_{1}v_{1}+m_{2}v_{2}=0[/tex]
Where:
m1 = mass of object 1
m2 = mass of object 2
v1= velocity of object 1
v2 = velocity of object 2
[tex]m_{1}v_{1}+m_{2}v_{2}=0[/tex]
[tex](450kg)(v1) + (2.75kg)(23.2m/s)=0[/tex]
[tex](450kg)(v1) + (63.8kg.m/s)=0[/tex]
[tex](450kg)(v1) =0 - 63.8kg.m/s[/tex]
[tex](450kg)(v1) =- 63.8kg.m/s[/tex]
[tex]v1 = \frac{-63.8k.m/s}{450kg} [/tex]
[tex]v1 = -0.14 m/s[/tex]
The cannon travelled -0.14m/s.
Notice that the value is negative, this means that it went the opposite direction it initially traveled or it traveled backwards.
What potential difference is needed to accelerate a he+ ion (charge +e, mass 4u) from rest to a speed of 1.0×106 m/s ? express your answer using two significant figures?
Answers
[tex]-\Delta U=\Delta K[/tex]
which can be rewritten as
[tex]-q \Delta V = \frac{1}{2}mv^2 [/tex]
where
[tex]q=+e = 1.6 \cdot 10^{-19}C[/tex] is the charge of the ion,
[tex]m=4u=4\cdot 1.67 \cdot 10^{-27}kg[/tex] is the mass of the ion,
[tex]v=1.0 \cdot 10^6 m/s[/tex] is the speed of the ion.
By using these values, we find the potential difference needed:
[tex]\Delta V = \frac{1}{2} \frac{mv^2}{-q}= \frac{1}{2} \frac{(4\cdot 1.67 \cdot 10^{-27}kg)(1.0 \cdot 10^6 m/s)^2}{-1.6 \cdot 10^{-19}C}= -20875 V=-21 kV [/tex]
and the negative sign means the final point is at lower voltage than the initial point, and this is correct, because the ion has positive charge and a positive charge travels naturally from higher voltages to lower voltages.
The potential difference required to accelerate the helium ion to a speed of [tex]1.0 \times {10^6}\,{{\text{m}} \mathord{\left/{\vphantom {{\text{m}} {\text{s}}}} \right.\kern-\nulldelimiterspace} {\text{s}}}[/tex] is [tex]\boxed{21\,{\text{kV}}}[/tex] or [tex]\boxed{20875\,{\text{V}}}[/tex].
Further Explanation:
The potential difference, through which the helium ion passes, provides the potential energy and this potential energy provided by the potential difference to the Helium ion leads to the increase in the kinetic energy of the ion.
The charge on the [tex]H{e^ + }[/tex] ion is equal to the charge of one electron and the mass of the helium atom is equal to the mass of [tex]4\,{\text{amu}}[/tex].
The expression for the conservation of the energy of the Helium ion in the potential difference is:
[tex]\Delta PE = \Delta KE[/tex]
Substitute [tex]q\Delta V[/tex] for [tex]\Delta PE[/tex] and [tex]\dfrac{1}{2}m{v^2}[/tex] for [tex]\Delta KE[/tex] in above expression.
[tex]\begin{aligned}q\Delta V &= \frac{1}{2}m{v^2} \hfill \\\Delta V &= \frac{{m{v^2}}}{{2q}} \hfill \\\end{aligned}[/tex]
Here, [tex]\Delta V[/tex] is the potential difference, [tex]m[/tex] is the mass of the ion, [tex]q[/tex] is the charge over the ion.
Substitute [tex]1.6 \times {10^{ - 19}}\,{\text{C}}[/tex] for [tex]q[/tex], [tex]\left( {4 \times 1.67 \times {{10}^{ - 27}}\,{\text{kg}}} \right)[/tex] for [tex]m[/tex] and [tex]1.0 \times {10^6}\,{{\text{m}} \mathord{\left/{\vphantom {{\text{m}} {\text{s}}}} \right.\kern-\nulldelimiterspace} {\text{s}}}[/tex] for [tex]v[/tex] in above expression.
[tex]\begin{aligned}\Delta V &= \frac{{\left( {4 \times 1.67 \times {{10}^{ - 27}}\,{\text{kg}}} \right){{\left( {1.0 \times {{10}^6}\,{{\text{m}} \mathord{\left/{\vphantom {{\text{m}} {\text{s}}}} \right.\kern-\nulldelimiterspace} {\text{s}}}} \right)}^2}}}{{2\left( {1.6 \times {{10}^{ - 19}}\,{\text{C}}} \right)}} \\&= \frac{{6.68 \times {{10}^{ - 15}}}}{{3.2 \times {{10}^{ - 19}}}}\,{\text{V}} \\&= 2{\text{0875}}\,{\text{V}} \\&\approx {\text{21}}\,{\text{kV}}\\\end{aligned}[/tex]
Thus, the potential difference required to accelerate the helium ion to a speed of [tex]1.0 \times {10^6}\,{{\text{m}} \mathord{\left/ {\vphantom {{\text{m}} {\text{s}}}} \right.\kern-\nulldelimiterspace} {\text{s}}}[/tex] is [tex]\boxed{21\,{\text{kV}}}[/tex] or [tex]\boxed{20875\,{\text{V}}}[/tex].
Learn More:
What type of mirror do dentist use https://brainly.com/question/997618 What is the threshold frequency ν0 of cesium? Note that 1 ev https://brainly.com/question/6953278 The amount of kinetic energy an object has depends on its https://brainly.com/question/137098Answer Details:
Grade: College
Chapter: Electrostatics
Subject: Physics
Keywords: Potential energy, potential difference, accelerate, kinetic energy, speed, helium ion, charge, significant figures, rest to a speed.
A person drives to the top of a mountain. On the way up, the person’s ears fail to “pop,” or equalize the pressure of the inner ear with the outside atmosphere. The pressure of the atmosphere drops from 1.010 x 10^5 Pa at the bottom of the mountain to 0.998 x 10^5 Pa at the top. Each eardrum has a radius of 0.40 cm. What is the pressure difference between the inner and outer ear at the top of the mountain?
a.
1.2 x 10^3 Pa
b.
1.1 x 10^5 Pa
c.
1.0 x 10^2 Pa
d.
1.2 x 10^2 Pa
Answers
And so the net force would be now calculated as P*A = 1200Pa*π*(0.40x10^-2m)^2 = 0.0603N
The pressure difference between the inner and outer ear at the top of the mountain is given by option a. 1.2 × 10³ Pa.
The pressure difference between the inner and outer ear at the top of the mountain can be calculated by evaluating the difference between atmospheric pressure at top and bottom of the lift. Let this difference be denoted as ΔP, then:
Δ P = P₁ - P₂
P₁ = pressure at the top of the lift = 1.010 × 10⁵ Pa
P₂ = pressure at the bottom of the lift = 0.998 × 10⁵ Pa
or, Δ P = (1.010 × 10⁵ Pa - 0.998 × 10⁵ Pa)
or, Δ P = 0.012 × 10⁵ Pa
or, Δ P = 1.2 × 10³ Pa
A charge of 50 µC is pushed by a force of 25 µN a distance of 15 m in an electric field. What is the electric potential difference? Recall that Fe = qE.
Answers
The electric potential difference is 7.5 V.
Electric potential difference between two points is defined as the work done in moving unit positive charge between the two points. Electric potential difference can also be defined as the work done W per unit charge q in an electric field.
[tex]\Delta V=\frac{W}{q}[/tex]......(1)
Work done by a force is the product of the force F and the displacement s made in the direction of the force. Assuming that the displacement is parallel to the line of action of the force,
[tex]W=F.s[/tex]......(2)
Rewrite equation (1) using equation (2).
[tex]\Delta V=\frac{Fs}{q}[/tex]......(3)
Substitute the given values of force, displacement and charge in the equation (3).
[tex]\Delta V=\frac{Fs}{q}\\ =\frac{(25*10^-^6N)(15m)}{(50*10^-^6C)} \\ =7.5V[/tex]
The potential difference between the two points is 7.5 V
A heat engine takes in 840 kJ per cycle from a heat reservoir. Which is not a possible value of the engine's heat output per cycle?
Answers
To determine an epicentral distance scientists consider the arrival times of what wave types
Answers
At the moment the acceleration of the blue ball is 9.40 m/s2, what is the ratio of the magnitudes of the force of air resistance to the force of gravity acting on the blue ball? use 9.81 m/s2 for the standard value of g at the location of the experiment.
Answers
The ratio of the magnitudes of the force of air resistance to the force of gravity acting on the ball is approximately 1:24.
The student is asking about the ratio of the force of air resistance to the force of gravity acting on a blue ball, when the ball has an acceleration of 9.40 m/s2. To calculate this ratio, we can use Newton's second law, F = ma, where F is the force, m is the mass of the ball, and a is the acceleration of the ball due to the net force acting on it. If we denote the force of air resistance as Fair and the force of gravity as Fgrav, we can write Fnet = Fgrav - Fair, since the air resistance works in the opposite direction of gravity.
Given that the acceleration due to gravity is approximately 9.81 m/s2, the force due to gravity (weight) can be expressed as Fgrav = mg. Here, the acceleration is less than g due to air resistance, thus we can write Fnet = ma = mg - Fair. Since the acceleration of the ball is given as 9.40 m/s2, we can now express Fair as mg - ma. Taking the ratio of Fair to mg (the weight), we get:
(mg - ma) / mg = (g - a) / g = (9.81 - 9.40) / 9.81.
Therefore, the ratio of the magnitudes of the force of air resistance to the force of gravity is equal to 0.0418, which simplifies to approximately 1:24.
A particle moving in the x direction is being acted upon by a net force f(x)=cx2, for some constant
c. the particle moves from xinitial=l to xfinal=3l. what is δk, the change in kinetic energy of the particle during that time? express your answer in terms of c and l.
Answers
[tex]\Delta K = W[/tex]
The work done on the particle is the integral of the force on dx:
[tex]W= \int\limits^{3L}_L {F(x)} \, dx = \int\limits^{3L}_L {cx^2} \, dx = \frac{26}{3}cL^3 [/tex]
So, this corresponds to the change in kinetic energy of the particle.
The change in kinetic energy during that time is : [tex]\frac{26}{3} cl^{3}[/tex]
Given data :
Direction of particle = x
Net force = F(x) = cx²
Initial position = l
Final position = 3l
Determine the change in kinetic energy during this timewe will apply the work energy theorem which is : ΔK = W
To determine change in kinetic energy we have to determine the work done on the particle.
Work done on particle ( W ) = [tex]\int\limits^3_l F({x}) \, dx[/tex] = [tex]\int\limits^3_l c{x^{2} } \, dx =[/tex] [tex]\frac{26}{3} cl^{3}[/tex]
Hence the change in kinetic energy during that time is : [tex]\frac{26}{3} cl^{3}[/tex]
Learn more about work energy theorem : https://brainly.com/question/22236101
You are asked to design a horizontal curve with a 40-degree central angle (' = 40) for a two-lane road with 11-ft lanes. the design speed is 70 mi/h and superelevation is limited to 0.06 f
a. True
b. Falset. give the radius, degree of curvature, and length of curve that you would recommend. 3.43 for the h
Answers
To design a horizontal curve for a two-lane road, you can calculate the radius, degree of curvature, and length of the curve using formulas.
Explanation:To design a horizontal curve, we need to calculate the radius, degree of curvature, and length of the curve. First, we can calculate the radius using the formula: R = (V2) / (15 * f), where R is the radius in feet, V is the design speed in miles per hour, and f is the superelevation. Plugging in the values, we get: R = (702) / (15 * 0.06) = 43,333.33 feet. The degree of curvature can be calculated using the formula: (180 * L) / (π * R), where L is the length of the curve in feet. Since the central angle is given as 40 degrees, the degree of curvature is also 40 degrees. Finally, we can calculate the length of the curve using the formula: L = (π * R * d) / 180, where d is the degree of curvature. Plugging in the values, we get: L = (π * 43,333.33 * 40) / 180 = 9,632.87 feet.
Learn more about Designing a horizontal curve here:https://brainly.com/question/32491308
#SPJ2
What is a property of a transparent object?
Answers
Two tuning forks of frequency 480 hz and 484 hz are struck simultaneously. what is the beat frequency resulting from the two sound waves?
Answers
Explanation:
The beat frequency is equal to the absolute value of the difference in frequency of the two waves. In other words, the number of beats per second is equal to the difference in frequency. It is due to the destructive and constructive interference. According to this interference, sound will be soft or loud.
Hence. the formula is:
Beat frequency = [tex]f_b = |f_2 - f_1|[/tex]
Since,
[tex]f_1 = 480Hz[/tex]
[tex]f_2 = 484Hz[/tex]
Therefore,
Beat frequency = [tex]f_b = |484 - 480|[/tex]
=> Beat frequency = [tex]f_b = 4Hz[/tex]
-i
a 13 kg sled is moving at a speed of 3.0 m/s. at which of the following speeds will the sled have tace as mucb as the kinetic
Answers
4.2 m/s
"a metal sphere of radius 5.00 cm is initially uncharged. how many electrons would have to be placed on the sphere to produce an electric field of magnitude 1.53 ✕ 105 n/c at a point 8.64 cm from the center of the sphere?"
Answers
[tex]E= k_e \frac{Q}{r^2} [/tex]
The problem asks to find the electric field at r=8.64 cm, while the radius of the sphere is R=5.00 cm, so r>R and we are exactly in this condition.
Re-arranging the previous formula, we can solve to find the total charge Q on the sphere. Using [tex]r=8.64 cm=8.64 \cdot 10^{-2}m[/tex] and [tex]E=1.53 \cdot 10^5 N/C[/tex], we find
[tex]Q= \frac{Er^2}{k_e} = \frac{(1.53 \cdot 10^5 N/C)(8.64 \cdot 10^{-2}m)^2}{8.99 \cdot 10^9 Nm^2C^{-2}} =1.27 \cdot 10^{-7}C[/tex]
This is the total charge on the surface. If we want to find the number of electrons composing this charge, we should divide the total charge by the charge of a single electron, e:
[tex]N= \frac{Q}{e} = \frac{1.27 \cdot 10^{-7}C}{1.6 \cdot 10^{-19}C}=7.9 \cdot 10^{11} [/tex]
and this is the number of electrons.
A wooden block has a mass of 562 g and a volume of 72 cm3. What is the density?
15 points !!!!!!!!!!!
Answers
Answer:
Density of the wooden block is [tex]7805.5\ kg/m^3[/tex]
Explanation:
It is given that,
Mass of the wooden block, m = 562 g = 0.562 kg
Volume of the block, [tex]V=72\ cm^3=7.2\times 10^{-5}\ m^3[/tex]
We need to find the density of the block. Mass per unit volume of an object is called its density. It is given by :
[tex]d=\dfrac{m}{V}[/tex]
[tex]d=\dfrac{0.562\ kg}{7.2\times 10^{-5}\ m^3}[/tex]
[tex]d=7805.5\ kg/m^3[/tex]
So, the density of the wooden block is [tex]7805.5\ kg/m^3[/tex]. Hence, this is the required solution.
Density of a Material
The density of a material is defined as the mass per unit volume
it formula is given as
Density = Mass/Volume
and the unit is g/cm^3
Explanation:
Given data
Mass = 562 g
Volume = 72 cm3
Hence the density is expressed as
Density = 562 /72
Density = 7.80 g/cm^3
therefore the density is 7.80 g/cm^3
for more information on density see the link below
https://brainly.com/question/17780219
A rock is thrown vertically upward from ground level at time t = 0. at t = t, it passes the top of the tower and ât later (i.e., when t = t + ât) it reaches the maximum height. what is the height of the tower? leave g as g â do not substitute with numbers
Answers
"The height of the tower is given by the equation:
[tex]\[ h = \frac{1}{2} g (t + \hat{t})^2 - \frac{1}{2} g t^2 \][/tex]
This equation represents the difference in height between the maximum height the rock reaches and the height it reaches at time \( t \) when it passes the top of the tower. Here, \( g \) is the acceleration due to gravity, \( t \) is the time it takes for the rock to reach the top of the tower, and \( \hat{t} \) is the additional time it takes for the rock to reach the maximum height after passing the top of the tower.
To find the height of the tower, we can simplify the equation:
[tex]\[ h = \frac{1}{2} g ((t + \hat{t})^2 - t^2) \][/tex]
[tex]\[ h = \frac{1}{2} g (t^2 + 2t\hat{t} + \hat{t}^2 - t^2) \][/tex]
[tex]\[ h = \frac{1}{2} g (2t\hat{t} + \hat{t}^2) \][/tex]
[tex]\[ h = g t\hat{t} + \frac{1}{2} g \hat{t}^2 \][/tex]
Since [tex]\[ u = g \hat{t} \][/tex]is the time it takes for the rock to reach the maximum height from the top of the tower, and at the maximum height the velocity of the rock is zero, we can use the kinematic equation for the final velocity \( v \) at the maximum height:
[tex]\[ v = u + g t \][/tex]
Here, \( u \) is the initial velocity (which is the velocity of the rock at the top of the tower), \( g \) is the acceleration due to gravity, and \( t \) is the time taken to reach the maximum height, which is \( \hat{t} \). At the maximum height, \( v = 0 \), so:
[tex]\[ 0 = u - g \hat{t} \][/tex]
[tex]\[ u = g \hat{t} \][/tex]
Now, we can substitute \( u \) back into the height equation:
[tex]\[ h = g t\hat{t} + \frac{1}{2} g \hat{t}^2 \][/tex]
[tex]\[ h = g t\left(\frac{u}{g}\right) + \frac{1}{2} g \left(\frac{u}{g}\right)^2 \][/tex]
[tex]\[ h = u t + \frac{1}{2} \frac{u^2}{g} \][/tex]
Since \( u t \) represents the distance the rock would have traveled in time \( t \) if it continued at a constant velocity \( u \), and \( \frac{1}{2} \frac{u^2}{g} \) represents the total height the rock would reach if it continued to move upward with initial velocity \( u \) and was only acted upon by gravity, the term \( u t \) is actually the height of the tower. Thus, the height of the tower is:
[tex]\[ h = u t \][/tex]
This is the final answer, and it shows that the height of the tower is the product of the initial velocity of the rock at the top of the tower and the time it takes to reach the top of the tower. The term[tex]\( \frac{1}{2} \frac{u^2}{g} \)[/tex]is not needed for the height of the tower, as it represents the additional height the rock reaches after passing the top of the tower until it reaches the maximum height."
If electrons of energy 12.8 ev are incident on a gas of hydrogen atoms in their ground state, what are the energies of the photons that are emitted by the excited gas?
Answers
When 12.8 eV energy electrons excite hydrogen atoms, the atoms are elevated to an energy level just below ionization. To determine the specific energy state, the energy formula for hydrogen atoms is used, then the energies of emitted photons are found by calculating the energy difference between the excited and final states.
Explanation:If electrons with an energy of 12.8 eV are incident on hydrogen atoms in their ground state, we first need to determine the energy level to which the hydrogen atoms are excited. The ground state energy of hydrogen is -13.6 eV. If 12.8 eV is provided, the electron reaches an energy level just below 0 eV (ionization energy), since 12.8 eV is not sufficient to completely ionize the atom (13.6 eV needed).
To find out which energy level the electron will jump to, we use the formula for the total energy of an electron in a hydrogen atom, En = (- 13.6 eV/n²), and solve for n.
Once the electron is excited, it will eventually drop back to a lower energy state, emitting a photon in the process.
The energy of the emitted photon can be calculated using the difference in energy levels, ΔE = E1 - Ef.
for a bohr model,how many protons,electrons,and neutron does Sodium has
Answers
A force of 35 n acts on an object which has a mass of 5.4 kg. what acceleration (in m/s2) is produced by the force
Answers
a = ∑F/m
a = 35 N / 5.4 kg
a = 6.5 m/s²
A grindstone, initially at rest, is given a constant angular acceleration so that it makes 20.0 rev in the first 8.00 s. what is its angular acceleration?
Answers
[tex]\theta = 20 rev = 20 rev \cdot \frac{2 \pi rad}{rev} =125. 6rad[/tex]
This is a rotational motion with constant angular acceleration [tex]\alpha[/tex], and with initial angular speed [tex]\omega _0 =0[/tex]. The angle covered in a time t is given by
[tex]\theta (t)= \omega_0 t+ \frac{1}{2} \alpha t^2 = \frac{1}{2} \alpha t^2 [/tex]
because the initial angular speed is zero.
Using t=8.00 s, we can find the value of angular acceleration:
[tex]\alpha = \frac{2 \theta}{t^2}= \frac{2 \cdot 125.6 rad}{(8.0 s)^2}=3.93 rad/s^2 [/tex]
The angular acceleration of a grindstone that makes 20 revolutions in 8 seconds from rest, convert the revolutions to radians and use the rotational kinematic equation, resulting in an angular acceleration of approximately 3.93 radians/s².
The angular acceleration of a grindstone that makes 20 revolutions in 8 seconds, starting from rest.
To find the angular acceleration, we can use the kinematic equation for rotational motion:
θ = ω₀t + 1/2αt²
where:
θ is the angular displacement in radians,
ω₀ is the initial angular velocity (which is 0 because it starts from rest),
t is the time in seconds,
and α is the angular acceleration in radians per second squared.
First, we convert the revolutions to radians:
20 revolutions * 2π radians/revolution = 40π radians
We then have:
40π radians = 0 + 1/2α(8²)
Solving for α gives:
α = (40π radians) / (1/2 * 64 s²)
α = 80π / 64 radians/s²
α ≈ 3.93 radians/s²
Therefore, the angular acceleration of the grindstone is approximately 3.93 radians/s².
Air is contained in a cylinder device fitted with a piston-cylinder. the piston initially rests on a set of stops, and a pressure of 200 kpa is required to move the piston. initially, the air is at 100 kpa and 238c and occupies a volume of 0.25 m3. determine the amount of heat transferred to the air, in kj, while increasing the temperature to 700 k. assume air has constant specific heats evaluated at 300 k.
Answers
Read more on Brainly.com - https://brainly.com/question/1581851#readmore
what is air resistance?
Answers
Air resistance is the pushing of air against an object that is moving. Both the air and the object rub together and this slows the down the object and making it use more energy to reach a required speed. If an object moves faster, the greater the air resistance it encounters.