Question

A lightbulb has an efficiency of 8.2%. how much light energy (not heat energy) is generated by the bulb every second if the bulb has a power of 21 w?

a. 13.20 j
b. 2.19 j
c. 1.72 j
d. 19.28 j

Answer 1

The light energy generated by the bulb every second is approximately 1.722 J.

Step-by-step explanation:

The efficiency of a lightbulb can be calculated by dividing the light energy output by the electrical energy input. In this case, the efficiency is given as 8.2%. To find the light energy generated by the bulb every second, we need to calculate the electrical power converted into light energy. The power of the bulb is given as 21 W, and the efficiency is 8.2%, so the light energy generated by the bulb every second can be calculated as:

Light Energy = Power x Efficiency
Light Energy = 21 W x 0.082
Light Energy = 1.722 J

Therefore, the light energy generated by the bulb every second is approximately 1.722 J.