Question

A lightbulb has an efficiency of 13.1%.How much light energy (not heat energy) is generated by the bulb every second if the bulb has a power pf 8W?

Answer 1

Answer:

1.048 W

Explanation: Given that a lightbulb has an efficiency of 13.1%.How much light energy (not heat energy) is generated by the bulb every second if the bulb has a power pf 8W?

The input power = 8W

The output power = ?

The efficiency = 13.1%

Using the formula below:

Efficiency = (power output / power input) × 100

13.1 = (Power output / 8 ) × 100

0.131 = power output / 8

Cross multiply to make the power output the subject of formula

Power output = 0.131 × 8

Power output = 1.048 W

Therefore, the light energy (not heat energy) generated by the bulb every second is 1.048 W