Question

Rajat wants to connect a fuse with an electrical appliance of rating 10 kW, 200 V. Which among the following fuses can he use?
(i) A fuse rated 25 A
(ii) A fuse rated 40 A
(iii) A fuse rated 50 A
(iv) A fuse rated 75 A

Only (i)
Only (iii)
Either (i) or (iii)
Either (iii) or (iv)
​

Answer 1

Answer:

he can use either fuse rated 50 A

or fuse rated 75 A

Answer 2

Only (iii) a fuse rated 50 A.

Explanation:

1. Power calculations has a formula as $P=VI$ where P denotes power, v denotes voltage and I denotes current.
2. Since V and P are given in the question ,we need to find the I (current) ,the formula can be rewritten as $I=P/V$.
3. Hence $I=(10000/200)A$.So $I=50 A$.We need to use the fuse which rated 50 A for the electrical appliance of rating 10 KW,200 V.