Question

A cell having emf = 5 V is connected to an external resistor R = 4.5 Ω. If the potential difference between the points ‘a’ and ‘b’ is 3.0 V, calculate the internal resistance r of the cell.​

Answer 1

Answer:

here    

Explanation:

emf of cell(E)= 5V

external resistance (R)=4.5ohm  

potentiol difference across wire (V)=3

internal resistance (r)=?

        Now,

current (I)=?

V=IR

3=I *4.5

I=3%4.5

NOW,

      E=IR +Ir

5=3+3%4.5r

2=3%4.5r

r=3ohm

  HENCE ,INTERNAL RESISTANCE IS 3 Ohm