Two cells of equal e.m.f. E and internal resi | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The total $e.m.f.$ of the series combination is $E_{eq} = E + E = 2E$.The total internal resistance is $r_{eq} = r_1 + r_2$.The total resistance o

Vedclass · Accepted Answer

$r_1 - r_2$

Vedclass · Answer

(B) The total $e.m.f.$ of the series combination is $E_{eq} = E + E = 2E$.The total internal resistance is $r_{eq} = r_1 + r_2$.The total resistance of the circuit is $R_{total} = R + r_1 + r_2$.The current $i$ flowing through the circuit is given by $i = \frac{2E}{R + r_1 + r_2}$.The potential difference $V_1$ across the first cell (with internal resistance $r_1$) is given by $V_1 = E - i r_1$.Given that $V_1 = 0$,we have $E - i r_1 = 0$,which implies $E = i r_1$.Substituting the value of $i$ into this equation:$E = \left( \frac{2E}{R + r_1 + r_2} \right) r_1$$1 = \frac{2r_1}{R + r_1 + r_2}$$R + r_1 + r_2 = 2r_1$$R = 2r_1 - r_1 - r_2$$R = r_1 - r_2$.

Two cells of equal $e.m.f.$ $E$ and internal resistances $r_1$ and $r_2$ $(r_1 > r_2)$ are connected in series. On connecting this combination to an external resistance $R$,it is observed that the potential difference across the first cell becomes zero. The value of $R$ will be

Similar Questions

In the previous problem,if the cells had been connected in parallel (instead of in series),which of the above graphs would have shown the relationship between total current $I$ and $n$ (number of cells)?

Why is the combination of cells done? Write its methods.

The $e.m.f.$ of a primary cell is $2 \ V$. When it is short-circuited,it gives a current of $4 \ A$. The internal resistance of the primary cell is ............. $\Omega$.

Write the equation for the equivalent electromotive force (emf) of cells connected in parallel.

Two non-ideal identical batteries are connected in parallel. Consider the following statements:
$(i)$ The equivalent e.m.f. is smaller than either of the two e.m.f.s.
$(ii)$ The equivalent internal resistance is smaller than either of the two internal resistances.

Vedclass Test Series

Exam Paper Generator

Online Exam Module