Q.39, find t he loss of energy during the collision.

Explanation

`K_(1)` = Total KE before collision `=1/2mv^(2)+1/2(3m)v^(2).`
`k_(2)=` Total KE after collision `=1/2(4m)V ^(2)`
Put the value of V found in Q. 39
`DeltaK=` loss of ` KE=K_(1)-K_(2)`
`K_(1)` total KE before collision `=1/2mv^(2)+1/2(3m)v^(2)=2mv^(2)`
`=2m5/8v^(2)asV=sqrt((5)/(8))v`
`=5/4mv^(2)`
`Deltak=` loss of KE during the collision
`=K_(1)-K_(2)`
`=2mv^(2)-5/4mv^(2)`
`DeltaK=3/4mv^(2)`