Two objects have equal kinetic energies. How do the magnitudes of their momenta compare? a. P1 < P2 b. P1 = P2 c. P1 > P2 d. Not enough information to tell

A golf ball m = 0.155 kg strikes a vertical concrete wall elastically with a horizontal velocity of v = 15 m/s.   a. Write an expression for the magnitude of the impulse I experienced by the ball.  b.  If the ball was in contact with the wall for t = .1s, what is the magnitude of the force F the ball experienced in N?  c.  If the ball rebounds with only half the velocity it comes in with, what is the magnitude of the impulse in kg m/s?  d.   Determine the magnitude of the change in kinetic energy in the above situation. Give your answer in joules.

B6

A 7400 kg truck traveling along a straight road at 14 m/s comes to a stop and remains stationary for several minutes. It then accelerates backward in reverse until it reaches 5.0 m/s in the opposite direction. What is the magnitude of the change in momentum of the truck for this entire process? A. 100,000 kg. m/s B. 140,000 kg. m/s C. 67,000 kgm/s D. 37,000 kgm/s O C O B OD O A

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1. For the purposes of this problem make sure you remember that the positive x direction is to the right. A 0.500 kg crash cart was rolling to the left at &; = -1.00 m/s. It was hit with a rubber hammer. Just afterwards the cart was rolling to the right with Uf = +2.50 m/s. The hammer was in contact with the cart for only 5.00 milliseconds. Remember to specify the direction in your answers as either postive or negative. (a) What is the change in momentum, Ap, for the cart? (b) What is the Impulse, I, applied by the hammer to the cart? (c) What is the average force, F, applied by the hammer to the cart? +x X+ Vf +X

The figure shows a distribution of several objects, in which m1 = 3.0 kg,   m2 = 2.0 kg, and m3 = 1.0 kg a. What is the x-coordinate of thesystem’s center of mass?A. 1.67 mB. 1.83 mC. 2.5 mD. 2.75 mE. None of these b. What is the y-coordinate of thesystem’s center of mass?A. 1.5 mB. 1.83 mC. 2.17 mD. 2.75 mE. None of these

A boy jumps straight up with an initial speed of 5.00 m/s. The boy’s mass is 60.0 kg, and the mass of the earth is about 6.00 x 1024kg. a. What is the initial recoil speed of the earth? b. How much time does it take for the two to reach their maximum separation? i.e., how long until the boy starts down? c. How far did the boy move in this time? d. How far did the earth move in this time?

. The linear impulse (I) of the force F= (3t) N for t= 4 seconds is: a. 40 N.m b. 20 N.m c. 16 N.m d. 12 N.m k= 10 N/m F= (3t) N

3. The total external force on an object is F=10t i + 60j (N). At t=0, the objects velocity is V=20j (m/s). At t=12 sec., the x-component of its velocity is 48 m/s. a. Determine the mass of the object. b. Determine the impulse applied to the object from t=0 to t=6 sec. c. Determine the objects velocity at t=6 sec.