A ball with a mass of # 23 kg# is rolling at #25 m/s# and elastically collides with a resting ball with a mass of # 2 kg#. What are the post-collision velocities of the balls?

1 Answer
Feb 8, 2016

Answer:

#v_(2a)=1,038 m/sec#
#v_(1a)=23,962 m/sec#

Explanation:

#Sigma P_b= Sigma P_a#
#Sigma P_b": sum of momentums before"#
#Sigma P_a:" sum of momentums after"#
#23*25+0=23*v_(1a)+2*v_(2a)#
#575=23*v_(1a)+2*v_(2a)#
#v_(1b)+v_(2b)=v_(1a)+v_(2a)#
#25+0=v_(1a)+v_(2a) " #
#v_(1a)=25-v_(2a)#
#575=23(25-v_(2a))+2*v_(2a)#
#575=575*v_(2a)-23*v_(2a)+2*v_(2a)#
#554*v_(2a)=575#
#v_(2a)=1,038 m/sec#
#25=v_(1a)+1,038#
#v_(1a)=25-1,038#
#v_(1a)=23,962 m/sec#