Physics (AS & A Level) · May / June 2022 · Paper 12 · Question 17

Researchers have developed a new type of filament lamp with an efficiency of 40%. Old-type filament lamps have an efficiency of 5.0%. The two types of lamp produce the same useful output power. What is the ratio $\dfrac{\text{input power to new type of lamp}}{\text{input power to old type of lamp}}$?

1. A0.13
2. B0.63
3. C1.6
4. D8.0

As printed in the paper