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

Given :
Rate of water flow = 2 km per hour
= \(\frac{2000}{60}\) m/min
= \(\frac{100}{3}\) m/min

Depth (h) of river = 3 m
Width (b) of = 40 m

So, we get,

Volume of water flowed in 1 min
= \((\frac{100}{3} × 40 × 3)\) \({m}^{3}\)
= 4000 \({m}^{3}\).

Therefore, in 1 minute, 4000 \({m}^{3}\) water will fall in the sea.