# Two Cells of Emfs 1.5 V and 2.0 V, Having Internal Resistances 0.2 Ω and 0.3 Ω, Respectively, Are Connected in Parallel. Calculate the Emf and Internal Resistance of the Equivalent Cell. - Physics

Two cells of emfs 1.5 V and 2.0 V,  having internal resistances 0.2 Ω and 0.3 Ω, respectively, are connected in parallel. Calculate the emf and internal resistance of the equivalent cell.

#### Solution

Given:
E1=1.5 V

E2=2 V

r1=0.2 Ω

r2 =0.3 Ω

The effective emf of two cells connected in parallel can be calculated as follows:

E_(eff) = (E_1r_2+E_2r_1)/(r_1+r_2)

=> E_(eff) = (1.5xx0.3+2.0xx0.2)/0.5 = 1.7 V

The effective resistance can be calculated as follows:

R_(eff)= (r_1r_2)/(r_1+r_2)

=> R_(eff)= (0.2xx.03)/0.50.12 Ω

Concept: Cells, Emf, Internal Resistance
Is there an error in this question or solution?