Q. How many 100 watt bulbs on the supply of 220 volts can be safely used with 5 ampere fuse?
A) 5
B) 8
C) 11
D) 20
✔ Correct Answer: 11
Exam Insight
To calculate the number of 100-watt bulbs that can be safely used with a 5-ampere fuse on a 220-volt supply, we use the formula: Power (W) = Voltage (V) × Current (I). The total power available with a 5-ampere fuse on a 220-volt supply is 220 × 5 = 1100 watts. Since each bulb uses 100 watts, the number of bulbs that can be safely used is 1100 ÷ 100 = 11 bulbs.