A ball is thrown straight up from height H while a second is thrown straight down. Neglect air resistance. After the balls have been released
(a) the one thrown up has the greater acceleration.
(b) the one thrown down has the greater acceleration.
(c) the accelerations are the same.
(d) neither ball accelerates after it has been released.
p

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.