A rifle of 20 kg mass can fire 4 bullets/s. The mass of each bullet is 35xx10^(-3)kg and its final velocity is 400ms^(-1). Then, what force must be applied on the rifle so that it does not move backwards while firing the bullets

A rifle of 20 kg mass can fire 4 bullets/s. The mass of each bullet is

1.	A rifle of 20 kg mass can fire 4 bullets/s. The mass of each bullet is 35xx10^(-3)kg and its final velocity is 400ms^(-1). Then, what force must be applied on the rifle so that it does not move backwards while firing the bullets
Answer» Solution :Law of conservation of MOMENTUM, `MV+4mv=0` `RARR V=-(4mv)/(M)=(4xx35xx10^(-3)xx400)/(20)=-2.8ms^(-1)` Force APPLIED on the rifle `F=(MV)/(t)=-(20xx2.8)/(1)=-56N`