Current drops by 3%. Now the percentage by which the incandescence of lamp decreases is:
- 0.3%
- 3%
- 6%
- No impact
Correct answer: 3. 6%
Explanation: P = I2R
ΔP = 2I(ΔI)R
OR
ΔP/P = {2I(ΔI)R}/{I2R} = 2ΔI/I = 2 × 3% = 6%
Current drops by 3%. Now the percentage by which the incandescence of lamp decreases is:
Correct answer: 3. 6%
Explanation: P = I2R
ΔP = 2I(ΔI)R
OR
ΔP/P = {2I(ΔI)R}/{I2R} = 2ΔI/I = 2 × 3% = 6%