Question

12 cells each of



e.M.F. 2v and initial resistance 0.1 ohm are connected (i) all in series (ii) all in parallel. Calculate the current sent in each case through a wire of resistance 2 o

Answer 1

(i) 7.5A; (ii) 0.95A

Explanation:

(i) When cells are connected in series their voltage adds.  

So, the value of current when 12 cells of 2V are connected in series will be,

E = I(R+r)  

Where “r” is the internal resistance of cell

r = 0.1*12 = 1.2 ohm

I = 12*2/2+1.2

I = 7.5A

(ii) When cells are connected in series their terminal voltage will be same. So,

I = V/R+r

I = 2/2+0.1

I = 0.95A