Question

A river $3m$ deep and $40m$ wide is flowing at the rate of $2km/h$. How much water will fall into the sea in a minute?

Answer 1

Given,

Depth of river, $h=3m$

Width of the river, $b=40m$

Rate of water flow $=2km/hour$

Step 1: Find out how much water will fall into the sea in a minute.

Rate of water flow $=2km/hour$

$$\begin{gathered} =\frac{2000}{60}m/min \\ =\frac{100}{3}m/min \end{gathered}$$

Now, the Volume of water flowing in $1$ $min$ $=$ $\frac{100}{3}\times 40\times 3$

$=$ $4000m^3$

Therefore, $4000m^3$of water will fall into the sea in a minute.