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Annieb
A 2.5 kg ball is dropped onto a concrete floor. It strikes the floor with a momentum of 20 kg • m/s and bounces away from the floor with a momentum of 16 kg • m/s. What is the change of momentum of the ball? (A) 4 kg • m/s (B) 8 kg • m/s (C) 32 kg • m/s (D) 36 kg • m/s (E) 40 kg • m/s A 2.5 kg ball is dropped onto a concrete floor. It strikes the floor with a momentum of 20 kg • m/s and bounces away from the floor with a momentum of 16 kg • m/s. What is the change of momentum of the ball? (A) 4 kg • m/s (B) 8 kg • m/s (C) 32 kg • m/s (D) 36 kg • m/s (E) 40 kg • m/s @Physics
change in momentum = finial momentum - intitial momentum
since it acts in opp direction
bcuz momentum is vector quantity u can not simply subtract them you have to be care ful with their vector directions|dw:1344183447716:dw|
I think question must specify that one is 20 and other is -16 since momentum is a vector quantity
@sauravshakya as he said ball is dropped and bounce so you can assume directions