First slide

Potential energy

Question

The radius of a well is 7m. Water in it is at a depth of 20m and depth of water column is 10m. Work done in pumping out water completely from the well is, (g = 10ms^–2)

Moderate

A

38.5 MJ
B

38.5 KJ
C

46.2 MJ
D

385 MJ

Solution

$\large w = mg\frac{h}{2} = \left( {v\rho } \right)g\frac{h}{2} = \frac{{22}}{7} \times {7^2} \times 10 \times {10^3} \times 10 \times \left( {20 + \frac{{10}}{2}} \right)J$
$\large = 385 \times {10^6}J$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App