A battery of emf 10 V and internal resistance 3 W is connected to a resistor. If the current in the circuit is 0.5 A, what is the resistance of the resistor? What is the terminal voltage of the battery when the circuit is closed?

Question

Philoid · Accepted Answer

The diagram is given as:

Given: Electromotive force (E) of battery = 10 volt.

Internal Resistance r of the battery = 3 Ω

Current in the Circuit (I) = 0.5 A

Let the resistance of the required resistor is R Ω

Let the Terminal voltage of the register be V.

As per Ω ’s law,

⇒

⇒R + r = 20 Ω

∵ r = 3Ω

Resistance of Resistor is 17 Ω.

Also, as per Ohm’s law,

⇒V = IR

⟹ V = 0.5A × 17Ω =

⇒ V = 8.5V

∴ Terminal voltage of the register is 8.5V.