Water falling from a 60 m high is to be used for generating electric power. If 9 × 105 kg of water falls per hour and half the gravitation potential energy can be converted into electric energy. How many 100 watt bulbs can be light ? ( g =10 m / s 2)

Question

Water falling from a 60 m high is to be used for generating electric power. If 9 × 105 kg of water falls per hour and half the gravitation potential energy can be converted into electric energy. How many 100 watt bulbs can be light ? ( g =10 m / s 2) (A)  7500 (B) 7700 (C) 1800 (D) 9000

Tardigrade Admin · Accepted Answer

Power generated = Energy/sec
Acc. to question,

P = \frac{m g h}{2} \times \frac{1}{t} = \frac{1}{2} \times \frac{9 \times 1 0 ^{5} \times 10 \times 60}{60 \times 60}

∴ P = 7.5 \times 1 0^{5} = 750000

Watt
then no. of 100 Watt bulb can be light is

\frac{750000}{100}

Bulb

= 7500

Q. Water falling from a $60 m$ high is to be used for generating electric power. If $9 \times 1 0^{5} k g$ of water falls per hour and half the gravitation potential energy can be converted into electric energy. How many $100$ watt bulbs can be light ? $(g = 10 m / s^{2})$

$7500$

$7700$

$1800$

$9000$

Power generated = Energy/sec
Acc. to question, $P = \frac{m g h}{2} \times \frac{1}{t} = \frac{1}{2} \times \frac{9 \times 1 0 ^{5} \times 10 \times 60}{60 \times 60}$
$∴ P = 7.5 \times 1 0^{5} = 750000$ Watt
then no. of 100 Watt bulb can be light is $\frac{750000}{100}$
Bulb $= 7500$

Q. Water falling from a 60m high is to be used for generating electric power. If 9×105kg of water falls per hour and half the gravitation potential energy can be converted into electric energy. How many 100 watt bulbs can be light ? (g=10m/s2)

7500

7700

1800

9000