Question

A river 2 metres deep and 45 metres wide is flowing at the rate of $3km$ per hour. Find the amount of water that runs into the sea per minute.

Answer 1

Area of cross sector of river = $2\times 45=90m^2$

So, water flowing into the sea = area of cross section \times rate of flowing water

$=90\times 3000$

$=270000m^3$

the water flowing per minute = $\frac{270000}{60}=4500m^3$