Question

15. An electric lamp whose resistance is 400 and a conductor of 20
resistance are connected to a 4V battery. Calculate the total resistance of
the circuit and the current through the circuit.​

Answer 1

★ Given :-

• Resistance of electric lamp = 400 Ω
• Resistance of conductor = 20 Ω
• Potential difference = 4 V

★ To find :-

⇨ Total resistance of the circuit

⇨ Current flowing through the circuit

★ Solution :-

For finding the total resistance in the circuit,

Total resistance = R₁ + R₂

→ Total resistance = 400 Ω + 20 Ω

∴ Total resistance = 420 Ω

By Ohms law,

Current flowing through the circuit = Voltage ÷ Resistance

⇒ Current = 4 ÷ 420

⇒ Current = 0.0095 Amperes or 95 milli Amperes

Know more:

1. Ohm's law states that Potential difference across the ends of a metallic wire in an electric circuit (Voltage) is directly proportional to current flowing, provided it's temperature remains same.