Question

A cell of emf 1.5 V is connected to an external resistance of 2ohm when the potential difference at the ends of the resistance is 1.2 V. Calculate the internal resistance of the cell

Answer 1

Answer:

V=IR

1.2= I ×2

I= 1.2 /2

I= 3/5 A

Then ..

emf = I (R+r)

1.5 = 3/5 (2+r )

3r = 1.5

r=0.5ohm (ans)