2018 · Q30
A circuit has a fuse having a rating of 5 A. What is the maximum number of 100 W – 220 V bulbs that can be safely connected in parallel in the circuit ?
General KnowledgePhysics
- A20
- B15
- C11
- D10
Explanation
Each 100 W, 220 V bulb draws current I = P/V = 100/220 = 0.4545 A. With a 5 A fuse, the maximum number of such bulbs in parallel is 5 / 0.4545 = 11. Connecting a twelfth bulb would draw about 5.45 A and blow the fuse. Hence 11 bulbs can be safely connected.