A boy throws a ball to another boy who throws it back with half the original speed. What is the ratio of the final kinetic energy to the initial kinetic energy of the ball?
A) 0.25
B) 0.50
C) 2.00
D) 0.75
E) 1.0
Question 2
The period of a pendulum is the time it takes the pendulum to swing back and forth once.
If the only dimensional quantities that the period depends on are the acceleration of gravity, g, and the length of the pendulum, L, what combination of g and L must the period be proportional to? Acceleration has dimensions of LT-2. A) g/L
B) gL2
C) gL
D)
E)
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