Question:

A car is driving through a rainstorm. Each raindrop of mass $\displaystyle 0.00005kg$ hits the windscreen with velocity of $\displaystyle 16 ms^{-1}$. If $\displaystyle 500$ raindrops hit the glass and run down the windscreen each second without bouncing, what force is exerted on the windscreen?

Attempt:

$\displaystyle m = 5.0 \times 10^{-5}kg \ , \ u = 16ms^{-1}$

don't know how to start, need help!