Two sources of equal emf are connected to an external resistance R. The internal resistance of the two sources are `R_1 and R_2(R_1gtR_1)`. if the potential difference across the source having internal resistance `R_2` is zero, then find vlaue of R.

Two cells, having the same emf, are connected in series through an external resistance R. Cells have internal resistance r_(1) and r_(2) (r_(1) gt r_(2)) respectively. When the circuit is closed, the potentail difference across the first cell is zero the value of R shown in the figure

A cell of emf 2 V and internal resistance 0.1Omega is connected to 3.9Omega external resistance. What will be the potential difference across the terminals of the cell?

Four resistance R_1,R_2,R_3 and R_4 are connected in parallel. The resultant resistance R is

Inductive resistance 25 ohm and capacitive resistance 75 ohm are connected across 250 V mains in series. Find the r.m.s. potential difference across inductor and capacitor.

Two cells of the same e.m.f. E but internal resistance r_1 and r_2 are connected in series to an external resistor R (fig. EP 3.25). What should be the value of R so that the potential difference across the terminals of the first cell becomes zero?