A ball with a mass of #4 kg# moving at #3 m/s# hits a still ball with a mass of #5 kg#. If the first ball stops moving, how fast is the second ball moving?

Question

1278 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-05-22T19:08:30

#v_1^'=-1/3 " "m/s#

#v_2^'=8/3 " "m/s#

#P_1=m_1*v_1#

#P_1=4*3=12" " kg*m/s#

#P_2=m_2*v_2#

#P_2=5*0=0#

#Sigma P_b=P_1+P_2#

#Sigma P_b=12+0=12 " "kg* m/s" total momentum before collision"#

#"Post collision velocities"#
#......................................#

#v_1^'=(2*Sigma P_b)/(m_1+m_2)-v_1#

#v_1^'=(2*12)/(4+5)-3#

#v_1^'=24/9-3#

#v_1^'=(24-27)/9#

#v_1^'=-3/9#

#v_1^'=-1/3 " "m/s#

#v_2^'=(2*Sigma P_b)/(m_1+m_2)-v_2#

#v_2^'=(2*12)/(4+5)-0#

#v_2^'=24/9#

#v_2^'=8/3 " "m/s#