Physics Test Chapters C3-C5 (Fall 2008) Name _________________________

The numbers in parenthesis give the relative value of each question.

All answers are to be to three significant figures.

You may use your formula sheet and a calculator.

Attach your formula sheet to this test when you turn finish the test.

(5) Clearly explain what is meant by an “inertial system” and under what different conditions you can consider a system to be inertial.

(5) You are placed in a room with no windows. Describe an experiment you could do that would enable you to know for sure whether or not you were in an inertial system. Completely describe your reasoning.

Circle the correct answer (3points)

Two identical balls floating in space collide. The white ball was initially moving to the right along the dotted line until it hit the black ball which was initially at rest. The white ball moves to the side as shown. After the collision the black ball has the same velocity as the white ball did initially. This outcome is a possibility.

A True

B False

(5) Explain the reason for your answer

(5) The momentum of two objects before they collide is shown by these two vectors: If the two objects stick together after the collision, draw the figure that shows how their final momentum is determined. Clearly label the final momentum.

(5) Would this figure change or not if you know that one of these objects was 10 times the mass of the other? Explain the reason for your answer.

A 300 kg astronaut in a space suit is on a space shuttle of mass 1000 kg and both are moving with a velocity of 100 m/second. The astronaut jumps from the shuttle and finds his velocity is 105 m/s at an angle of 15° with his original direction of motion. Find the magnitude and direction of the velocity of the shuttle after he jumps off.

(5) State the principle to be used in solving this problem. Be sure to include the reason you think the principle can be applied in this case.

(10) Explain in detail how this principle is used to solve the problem.

(5) Draw a clear figure and that shows the data. (5) Draw a vector diagram of this.

(10) Set up the equations and solve the problem.

A 70 kg astronaut is in a 1000 kg space shuttle that is far from any objects and is sitting still. The length of the shuttle is 20 m. The astronaut is at one end of the shuttle and jumps, pushing against that end of the shuttle, with a velocity of 5 m/s to the other end of shuttle where he stops. How far does the shuttle move when he goes from one end to the other?

(5) State the principle to be used in solving this problem. Be sure to include the reason you think the principle can be applied in this case.

(10) Clearly explain how the principle is applied to solve the problem.

(5) Draw a clear figure and show the data.

(10) Write the equations and solve them to find the answer.

(10) When the man is flying though the center of the shuttle at 5 m/s, what is happening to the shuttle? Completely describe what is happening to the shuttle at this time. If the shuttle is moving, give its velocity, both direction and magnitude.

(5) What happens to the center of mass of the man-shuttle system as the man moves from one end of the shuttle to the other?

(10) Find the z coordinate of the center of mass of a system consisting of 4 particles, 2 kg at (1,1,1), 5 kg at the origin, 3 kg at (2,0,3) and 5 kg at (0,2,0).