Two non-ideal batteries are connected in parallel. Consider the following statements:- (A) The equivalent emf is smaller than either of the two emfs. (B) The equivalent internal resistance is smaller than either of the two internal resistances.

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KollegeApply · Accepted Answer

B is correct but A is wrong The equivalent emf \epsilon_0, when two non-ideal batteries of emfs \epsilon_1 and \epsilon_2 and internal resistances r1 and r2 respectively are connected in parallel to each other, is given by:- \epsilon_0 = \frac{\epsilon_1 r_1 + \epsilon_2 r_2}{r_1 + r_2} Thus, the equivalent emf is greater than either of the emfs. Thus, statement A is wrong. For the parallel combination of the batteries of internal resistance r1 and r2, the equivalent internal resistance r is given as r = r_1 r_2/r_1 + r_2 Thus, the value of the resultant resistance is even smaller than either resistance.

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