Question

Two cells of emf E each andinternal resistance r1 and r2 are connected in series across a liad reisitance R.if potential differenc across the first cell is zero,then find the relation between R,r1 and r2​

Answer 1

Q]____?

Current I from positive electrodes of both are equal.

I = Eeq/ R+req = 2E / R+( r1+r2)

Potential difference across first cell

= Vᴀ - Vʙ= 0

=> E - Ir1 = 0

=> E - [2E/ R+(r1 + r2)] r1 = 0

=> R + r1 + r2 - 2r1 = 0

=> R + r2 - r1 = 0

=> r1 = R + r2

=> R = (r1 - r2)

Therefore ans is R=(r1 - r2)

Answer 2

Answer:

Answer is R=r1-r2

Hope it will be helpful ☺️ thank you!!!