A 20-g bullet moving at 1000 m/s is fired through a one-kg block of wood emerging at a speed of 200 m/s. What is the kinetic energy of the block that results from the collision if the block had not been moving prior to the collision and was free to move?
a. 10 kJ
c. 0.16 kJ
b. 9.8 kJ
d. 0.13 kJ
[Ques. 2] Two point charges of values +3.4 mC and +6.6 mC, respectively, are separated by 0.20 m. What is the potential energy of this 2-charge system? (ke = 8.99 109 Nm2/C2)
a. +1.0 J
c. -0.75 J
b. -5.0 J
d. +0.50 J
[Ques. 3] A 20-g bullet moving at 1000 m/s is fired through a one-kg block of wood emerging at a speed of 200 m/s. If the block had been originally at rest and is free to move, what is its resulting speed?
a. 800 m/s
c. 16 m/s
b. 80 m/s
d. 8 m/s
[Ques. 4] Which of the following characteristics are held in common by both gravitational and electrostatic forces when dealing with either point masses or charges?
a. potential energy is a function of distance of separation
b. forces are conservative
c. inverse square distance law applies
d. all of the above choices are valid
[Ques. 5] Three satellites are launched into space connected together. Once in deep space, an explosive charge separates the three satellites and they move apart. The satellites each have different masses with m1 < m2 < m3 . Which of the following statements is always true?
a. The one with mass m1 receives the greatest impulse.
b. The one with mass m3 receives the greatest impulse.
c. The all must receive equal impulses.
d. Although one or more of the above statements could be true in special cases, they are not always true.
[Ques. 6] If the distance between two negative point charges is increased by a factor of two, the resultant potential energy is what factor times the initial potential energy?
a. 2
c. 1/4
b. 1/2
d. 4
[Ques. 7] A lump of clay is thrown at a wall. A rubber ball of identical mass is thrown with the same speed toward the same wall. Which statement is true?
a. The clay experiences a greater change in momentum than the ball.
b. The ball experiences a greater change in momentum than the clay.
c. The clay and the ball experience the same change in momentum.
d. It is not possible to know which object has the greater change in momentum.
[Ques. 8] In which case does an electric field do positive work on a charged particle?
a. A negative charge moves opposite to the direction of the electric field. b. A positive charge completes one circular path around a stationary positive charge.
c. A positive charge is moved to a point of higher potential energy.
d. A positive charge completes one elliptical path around a stationary positive charge.
[Ques. 9] A miniature spring-loaded, radio-controlled gun is mounted on an air puck. The gun's bullet has a mass of 5.00 g, and the gun and puck have a combined mass of 130 g. With the system initially at rest, the radio controlled trigger releases the bullet causing the puck and empty gun to move with a speed of 0.500 m/s. What is the bullet's speed?
a. 4.80 m/s
c. 48.0 m/s
b. 13.0 m/s
d. 12.5 m/s
[Ques. 10] A free electron is in an electric field. With respect to the field, it experiences a force acting:
a. perpendicular.
c. parallel.
b. along a constant potential line.
d. anti-parallel (opposite in direction).
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