A body of mass 4.2kg moving with a velocity 10m/s dues east hit a ststionery body of 2.5kg if they stick together after collision and move velocity v dues east.Calculate the value of v  

A body of mass 4.2kg moving with a velocity 10m/s dues east hit a ststionery body of 2.5kg if they stick together after collision and move velocity v dues east.Calculate the value of v