Question

A voltmeter has a resistance of

100 Ω. What will be its reading when it

is connected across a cell of emf 2 V and

internal resistance 20 Ω?​

Answer 1

Question

A voltmeter has a resistance of 100 Ω. What will be its reading when it

is connected across a cell of emf 2 V and internal resistance 20 Ω?​

Answer

Given ,

Resistance , R = 100 Ω

Internal resistance , r = 20 Ω

Voltage , V = 2 v

Here we need apply Ohm's law for finding the current in the circuit.

⇒ V = I R(eq)

⇒ V = I ( R + r )

⇒ 2 = I ( 100 + 20 )

⇒ 2 = I ( 120 )

⇒ I = 1 / 60

⇒ I = 0.0167 Ampere