An electric bulb of resistance 20Ω and a a resistance wire of 4Ω are connected in series with a 6 V battery.
(a) Total resistance of the circuit.
(b) Current through the circuit.
(c) Potential difference across the electric bulb.
(d) Potential difference across the resistance wire.
Given:
Resistance of the electric bulb = 20 Ω
Resistance of the wire = 4 Ω
Potential difference of the battery = 6 V
(A.)
The total resistance of the circuit = 20Ω + 4Ω =24 Ω
(B.)
Everything is connected in series, Hence
The current through the circuit = current through the bulb = current through the conductor = I
The current through the circuit, I = VR
I = 624
The current through the circuit, I = 0.25 amp
(C.)
We know V = I × R
The potential difference across the electric lamp = 0.25 ×20
= 5 volt
(D.)
The potential difference across the resistance wire = 0.25 × 4
= 1 volt