Question

20ohm shunt to balance length 125 cm

25ohm shunt to balance 140 cm

Find original balance length without shunt and internal resistance of cell

Answer 1

Answer

The internal resistance of cell is given by :-

r=(

12

4

−1)R (l

1

: balance length without shunt

l

2

: balance length with shunt

R: connoted shunt in series with cell)

⇒r=(

100

150

−1)×2

=(1.5−1)×2=1Ω (Ans)