Two identical balls are thrown directly upward, ball A at speed v and ball B at speed 2v, and they feel no air resistance. Which statement about these balls is correct?
A) Ball B will go four times as high as ball A because it had four times the initial kinetic energy.
B) Ball B will go twice as high as ball A because it had twice the initial speed.
C) The balls will reach the same height because they have the same mass and the same acceleration.
D) At their highest point, the acceleration of each ball is instantaneously equal to zero because they stop for an instant.
E) At its highest point, ball B will have twice as much gravitational potential energy as ball A because it started out moving twice as fast.
A
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