A baseball infielder, mass 78.0 kg, jumps up with velocity 3.50 m/s and catches a 0.195-kg baseball moving horizontally at 55.0 m/s. Of the following, which is closest to the final momentum of the system, infielder and baseball?
a. 273 kg/m/s
b. 328 kg/m/s
c. 284 kg/m/s
d. 240 kg/m/s
e. 293 kg/m/s
[Ques. 2] A 1 000-kg vehicle is moving in the positive y-direction along the y-axis at 10 m/s. A 2 000-kg vehicle is moving in the positive x-direction at along the x-axis at 20 m/s. The vehicles collide and stick together. They move as a single object in a direction as measured counterclockwise from the x-axis immediately after the collision. What is the value of tan ?
a. 2.0 b. 4.0
c. 0.50 d. 0.25
[Ques. 3] A 75.0-kg halfback running north with a speed of 11.0 m/s is tackled by a 80.5-kg opponent running south at 7.5 m/s. The collision is perfectly inelastic. Compute the velocity of the two players just after the tackle.
a. 9.2 m/s south
b. 1.4 m/s south
c. 1.4 m/s north
d. 40 m/s north
e. 9.2 m/s north
[Ques. 4] A billiard ball is moving in the x-direction at 30.0 cm/s and strikes another billiard ball moving in the y-direction at 40.0 cm/s. As a result of the collision, the first ball moves at 50.0 cm/s, and the second ball stops. What is the change in kinetic energy of the system as a result of the collision?
a. 0
b. some positive value
c. some negative value
d. No answer above is correct.
[Ques. 5] A billiard ball is moving in the x-direction at 33.4 cm/s and strikes another billiard ball moving in the y-direction at 38.9 cm/s. As a result of the collision, the first ball moves at 50.6 cm/s, and the second ball stops. In what final direction does the first ball move?
a. in the x-direction
b. at an angle of 49.4 ccw from the x-direction
c. at an angle of 40.6 ccw from the x-direction
d. at an angle of 56.6 ccw from the x-direction
e. Such a collision cannot happen.
[Ques. 6] If a two-body collision is not head-on, then we may always assume that:
a. momentum is conserved.
b. kinetic energy is conserved.
c. neither momentum nor kinetic energy are conserved.
d. both momentum and kinetic energy are conserved.
[Ques. 7] Three masses are moving along the x-axis. Their masses and velocities are m1 = m with v1 = v, m2 = 2m with v2 = 2v, and m3 = 3m with v3 = 3v (the minus sign indicating this velocity is in the negative x-direction). The three masses collide and stick together in a completely inelastic collision. What is the resultant velocity of the combined mass?
a. 0, since their combined momentum is zero.
b. 2v/3
c. 14v/3
d. v
[Ques. 8] Mitch throws a 130-g lump of clay at a 590-g target, which is at rest on a horizontal surface. After impact, the target, including the attached clay, slides 2.8 m before stopping. If the coefficient of friction is = 0.50, find the speed of the clay before impact.
a. 6.4 m/s
b. 33 m/s
c. 29 m/s
d. 0.62 m/s
e. 34 m/s
[Ques. 9] A neutron in a nuclear reactor makes an elastic head-on collision with a carbon atom initially at rest. (The mass of the carbon atom is 12 times that of the neutron.) What fraction of the neutron's kinetic energy is transferred to the carbon atom?
a. 14.4
b. 28.4
c. 41.4
d. 56.6
[Ques. 10] A 25.0-kg object sitting at rest is struck elastically in a head-on collision with a 20.5-kg object initially moving at +4.0 m/s. Find the final velocity of the 25.0-kg object after the collision.
a. 0.90 m/s
b. 3.6 m/s
c. +6.6 m/s
d. +3.6 m/s
e. +15 m/s
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