WAEC - Physics (1994 - No. 32)
A cell of e.m.f. 1.5V and internal resistance of 2.5Ω is connected in series with an ammeter of resistance 0.5W and a resistor of resistance of 7.0Ω. Calculate the current in the circuit.
0.15A
0.20A
2.10A
3A
6.6A
Giải thích
I =\(\frac{E}{R+r} = \frac{1.5}{2.5+0.5+7}\) = 0.15A