1. Consider a gas of molecules in thermal equilibrium with temperature T and a number n per area, confined to a 2-D flat surface.

-What is the kinetic energy per area of the gas?

-What is the force per length that these molecules exert on an edge of the surface?

-If there are diatomic molecules, what is the rotational energy per area of the gas? (Assume that each atom of each molecules is confined to a flat surface)

Can someone explain to me Bohr's model of hydrogen and Bohr Selection Rule

An object with m₁ = 5kg is attached to a spring of negligible mass. This mass/spring combination is then slid horizontally on a frictionless surface with a velocity of 5m/s towards a stationary object with m₂ = 6kg. Upon impact, the spring compresses, then we examine two cases. First, find the velocities of the two objects assuming the spring completely relaxes again after the interaction. Second, assume that m₂, after they separate, slides up a frictionless incline.

(a) What is the relative speed of the masses when the spring is maximally compressed?

(b) When the spring is completely compressed, how much potential energy does it have?

(c) If the spring constant is k = 2000 N/m, by how much (what distance) is the spring compressed at that point?

(d) If the spring relaxes while still on at ground, what is the kinetic energy of m₂ just before it slides up the hill?

(e) If there is no friction on the hill, how high up the hill does m₂ go?

(f) If there is friction on the hill, and m₂ goes up the hill to a height of 0.5 meters, how much energy was dissipated?

An 18-kg sled starts up a 36 ∘ incline with a speed of 2.2 m/s . The coefficient of kinetic friction is μk= 0.25.

How far up the incline does the sled travel?

What condition must you put on the coefficient of static friction if the sled is not to get stuck at the point determined in Part A?

If the sled slides back down, what is its speed when it returns to its starting point?

How did the Conservation of Momentum allow Chadwick to prove the existence of the neutron when it was believed that the combination of protons and electrons alone made atoms?

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Question: This is my second time posting this:   Question: I have been working on this and I have...

This is my second time posting this:  

Question: I have been working on this and I have done it. But I am not sure what velocity versus time plot,...

I have been working on this and I have done it. But I am not sure what velocity versus time plot, acceleration versus time plot, position versus time plot. I just want to make sure I am doing it the right way. Please be sure to do it the right way and provide a correct answer.  

Go to   http://phet.colorado.edu/en/simulation/moving-man and download the simulation saving as a file. Click on moving-man_en.jar in the download window. Accept the agreement and begin the simulation.   You will do that for all the experiments in the class. Do not delete the given content in the assignment. Highlight your answers using yellow color

When the simulation begins, click on the Charts tab. Click on the bottom negative magnifying glass (lower right corner) until the time scale reads 20 sec. Similarly, set the acceleration a maximum scale of 4.7 m/s². Then set the maximum velocity scale to 5.8 m/s. Leave the maximum position at ±10 m.

In all of the following simulations, when one of the graphs is about to go outside the given scale, Pausethe simulation.

Set position = -10.0 m, velocity = 0.0 m/s, and acceleration = 0.10 m/s² by typing the value in the corresponding box.   Clear the simulation and then Play the simulation, pausing when the position reaches the scale limit of 10 m.

[Type your answer here]

(a) Describe the position versus time plot.

b) Describe the velocity versus time plot.

[Type your answer here]

c) Describe the acceleration versus time plot.

[Type your answer here]

2. Set the position = 10.0 m, the velocity = -4.0 m/s, and the acceleration = 0.45 m/s²

Click Clear at the bottom and then Play. Pause the simulation when the position is just about to exceed 10m.

a) Describe the position versus time plot.

[Type your answer here]

b) Describe the velocity versus time plot.

[Type your answer here]

c) Describe the acceleration versus time plot.

[Type your answer here]

An air-track cart with mass m1=0.28kg and initial speed v0=0.80m/s collides with and sticks to a second cart that is at rest initially.

Part A

If the mass of the second cart is m2=0.53kg, how much kinetic energy is lost as a result of the collision?

Express your answer to two significant figures and include appropriate units.

What is the difference in finding magnitude of a force on a charge and finding the net electric force acting on a charge?

If given three charges set at a certain places set on a triangle, how would you find the magnitude of a force on one of the charges? Please create a simple example and show each step clearly and explanation for what to do in each step esecially on how to find, set up, and use the components to add the forces together and determine the vector sum of forces.

If given four charges set at a certain places set on a square, how would you find the magnitude of a force on one of the charges? Please create a simple example and show each step clearly and explanation for what to do in each step esecially on how to find, set up, and use the components to add the forces together and determine the vector sum of forces.

If an electron is moving at a certain speed and at a certain angle to a magnetic field, how do I find the force of that electron? Please give me the equation and the rearranged eqation for finding the answer. Please tell me what each letter of the equation stands for and their units. Please create a simple example and take me step by step on how to solve and include the final units of the answer.

1.
A) Mountain rescue officers trigger an avalanche by firing a gun at a distant mountain slope. The muzzle velocity of the gun is 190 m/s. The gun muzzle is at sea level (y=0). The horizontal and vertical distance from the gun to the slope is 640 m and 240 m, respectively. Find the lowest angle between the barrel of the gun and the horizontal plane.
Round your answer to the nearest tenth of degree.

B) The mountain rescue officers trigger the avalanche by firing a gun at a distant mountain slope. The muzzle velocity of the gun is 140 m/s. The gun is at the sea-level (y=0). The horizontal and vertical distance from the gun to the slope is 790 m and 210 m, respectively. Find the highest angle between the barrel of the gun and the horizontal plane that results in direct hit.
Round your answer to the nearest tenth of degree.

Find a relationship between the equilibrium temperature of a spherical object and the distance from the sun in terms of the Sun's emission temperature

Describe why the sound of an oncoming siren changes as it passes you on the street. Please include terms such as blue and red shift. What is one way this is used in astronomy?

The law of entropy can also be called the law of increasing disorder; but this law seems to contradict the existence of living organisms that are able to organize chemicals into organic molecules. Explain how living things seem to be able to defy the laws of thermodynamics in terms of the universe's entropy due to life processes and the entropy within a living organism.

Comment just says "a"...?

Research how an internal combustion engine operates. Describe four steps of a combustion cycle. What materials go in and out of the engine during each step? How many cylinders are involved in one cycle? What energy processes take place during each stroke? In which steps is work done?

A 1246 kg weather rocket accelerates upward at 11.7 m/s². It explodes 1.6 s after liftoff and breaks into two fragments, one twice as massive as the other. Photos reveal that the lighter fragment traveled straight up and reached a maximum height of 571 m. What were the speed of the heavier fragment just after the explosion?