A sphere of mass 2 kg moving at 36 km/hrcollides head on with another sphere of mass 3 kg kept at rest . If after collisionboth spheres moves together then kinetic energy decreases by collision will be ……….

A sphere of mass 2 kg moving at 36 km/hrcollides head on with another

1.	A sphere of mass 2 kg moving at 36 km/hrcollides head on with another sphere of mass 3 kg kept at rest . If after collisionboth spheres moves together then kinetic energy decreases by collision will be ……….
Answer» 40 J 60 J 100 J 140 J SOLUTION :MOMENTUM is conserved in COLLISION ` :.M_(1)v_(1) =m_(2)v_(2)=(m_(1)+m_(2))V` Where V = combine velocity of SPHERES ` 2XX 10 +3 + 3 xx 0 = (2 + 3)V` ` :. 5V = 20` ` :. V = 4` m/s Initial kinetic of system`K_(1)=1/2m_(1)v_(1)^(2) [ :. v_(2) = 0 ] ` ` = 1/2 xx2xx100` ` = 100 J ` Final kinetic energy `K_(2) =1/2 (m_(1)+m_(2))V^(2)` `=1/2 (2+3)(4)^(2)` ` =(5xx16)/2` = 40 J ` :. ` Kinetic energy decreases = `100 J - 40 J ` = 60 J