# From a tap of inner radius 0.75 cm, water flows at the rate of 7 m per second.

Question:

From a tap of inner radius 0.75 cm, water flows at the rate of 7 m per second. Find the volume in litres of water delivered by the pipe in one hour.

Solution:

Given data is as follows:

r = 0.75 cm

Water flow rate = 7 m/sec

Time = 1 hour

We have to find the volume of water that flows through the pipe for 1 hour.

Let us first convert water flow from m/sec to cm/sec, since radius of the pipe is in centimeters

We have,

Water flow rate = 7 m/sec

= 700 cm/sec

Volume of water delivered by the pipe is equal to the volume of a cylinder with h = 7 m and r = 0.75 cm. Therefore,

Volume of water delivered in 1 second = 22/7 × 0.75 × 0.75 × 700

We have to find the volume of water delivered in 1hour which is nothing but 3600 seconds.

Therefore, we have

Volume of water delivered in 3600 seconds $=22 / 7 \times 0.75 \times 0.75 \times 700 \times 3600=4455000 \mathrm{~cm}^{3}$.

We know that $1000 \mathrm{~cm}^{3}=1$ litre

Therefore,

Volume of water delivered in 1 hour = 4455 liters

Therefore, Volume of water delivered by the pipe in 1 hour is equal to 4455 liters.