A current of 1 ampere flows in a series circuit containing an electric lamp and a conductor of 5 Ω
A current of 1 ampere flows in a series circuit containing an electric lamp and a conductor of 5 Ω when connected to a 10 V battery. Calculate the resistance of the electric lamp. Now if a resistance of 10 Ω is connected in parallel with this series combination, what change (if any) in current flowing through 5 Ω conductor and potential difference across the lamp will take place? Give reason.
2 Answers
(i) 5 Ω (ii) Hint— Calculate the total resistance of the circuit. There will be no change in current flowing through 5 Ω conductor. Also there will be no change in potential difference across the lamp either.
(1)
Let R be the resistance of the electric lamp. In series total resistance = 5 + R
I = v/r
1 = 10/5 + R
R = 5 ohm
2) V across Lamp + conductor = 10 V
V across Lamp = I × R
= 1 x 5
= 5 Volt