Physics Circle home Student Login

Home›Chapters›Current Electricity PYQs›Cells: EMF, Internal Resistance & Combinations›Question 37

JEE Main 2018 · Cells: EMF, Internal Resistance & Combinations

Cells: EMF, Internal Resistance & Combinations question from JEE Main 2018

Q37JEE Main 2018Medium

Cells: EMF, Internal Resistance & Combinations

Two batteries with e.m.f 12 V and 13 V are connected in parallel across a load resistor of 10 Ω\Omega. The internal resistances of the two batteries are 1 Ω\Omega and 2 Ω\Omega respectively. The voltage across the load lies between:

Show answer and solution

Answer: (c)

  1. Cells in parallel with a load (Millman): V=E1/r1+E2/r21/r1+1/r2+1/RV = \dfrac{E_1/r_1 + E_2/r_2}{1/r_1 + 1/r_2 + 1/R}.
  2. V=12/1+13/21+0.5+0.1=18.51.6V = \dfrac{12/1 + 13/2}{1 + 0.5 + 0.1} = \dfrac{18.5}{1.6}
  3. V=11.56 VV = 11.56\text{ V}
  4. So the answer is (c) between 11.5 V and 11.6 V.
Report a mistake

More questions on Cells: EMF, Internal Resistance & Combinations