A student is given 4 identical batteries having emf 1.5 Veach and internal resistance of 0.1`Omega` each. The student is asked to connect them in assisting manner. By mistake he connects one battery in reverse way. The resultant emf and resultant internal resistance offered by the combination is ....

Options

A. 3V, 0.2 `Omega`
B. `4.5 V , 0.3 Omega`
C. `3V, 0.4 Omega`
D. `6.0 V, 0.4 Omega`

Answer

C

Explanation

`3V, 0.4 Omega`

Equivalent emf `esillon = 1.5 + 1.5 + 1.5 = 3.0 V ` and equivalent internal resistance r = `r_(1) + r_(2) + r_(3) + r_(4) `
= 0.1 + 0.1 + 0.1 + 0.1
= 0.4 `Omega`