# Solve this:

Force is rate of change of momentum.

F=d(Mv)/dt = d(M)/dt * v = M' * v ———————(1)

Where M' is the mass water stream flowing per second

M' is given by (density)*(volume flow rate) (M =ρV) and volume flow rate is obtained by (area of cross section)*velocity V =Av

. So we get M'=ρ*A*v

Substituting this in (1) we get

F=ρ*A*v*v

So correct option is b

Regards

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