N bullets each of mass m kg are fired with a velocity v m/s at the rate of n bullets per second upon a wall. The reaction offered by the wall to the bullets is given by

Nmv nmv $\frac{nmv}{N}$ $\frac{Nmv}{n}$

nmv

No. of bullets striking the wall per second is n. Momentum of each bullet is mv. Change in momentum per second is nmv. Force = Rate of change of momentum = nmv