JAMB - Physics (2017 - No. 9)
A cell of internal resistance 2Ω supplies current to a 6Ω resistor. The efficiency of the cell is
12.0%
25.0%
33.3%
75.0%
Vysvetlenie
Internal resistance determine the maximum current that can be supplied
Efficiency = \(\frac{R}{R+ r}\) × 100
= \(\frac{6}{8}\) × 100
= 75%
Efficiency = \(\frac{R}{R+ r}\) × 100
= \(\frac{6}{8}\) × 100
= 75%