Question

A river 10 m deep and 100 m wide is flowing at the rate of 7.2 km/h. Find the quantity of the water that runs into the sea per second.

Answer 1

Soln:- speed=7.2 km/h
= 7.2×1000 m /60×60 s
=7200m /3600 s
=2 m/s
So distance travelled by water in 1 s=2m
l=2m
b=100m
h=10m

Volume =(2×100×10)m^3
=2000 m^3
1m^3=1000 l
2000m^3=2000×1000 l
=2000000 l

Hence 2000000 l of water flow per second

Answer 2

Answer

Soln:- speed=7.2 km/h

= 7.2×1000 m /60×60 s

=7200m /3600 s

=2 m/s

So distance travelled by water in 1 s=2m

l=2m

b=100m

h=10m

Volume =(2×100×10)m^3

=2000 m^3

1m^3=1000 l

2000m^3=2000×1000 l

=2000000 l

Hence 2000000 l of water flow per sec