Define internal resistance of a cell. Prove that `r ~= ((E)/(V) - 1)R`, where R is the external resistance used.

In a closed circuit, the e.m.f. and internal resistance of the generator are E and r respectively. If the external resistance in the circuit is R, then Ohm's law has the form

Two cells of emf 3V and 5V and internal resistance r_(1) and r_(2) respectively are in series with an external resistance R. if the p.d. across 1 st cell is zero, then R is

A battery of emf epsilon and internal resistance r sends currents I_(1) and I_(2) , when connected to external resistance R_(1) and R_(2) respectively. Find the emf and internal resistance of the battery.

An total resistance R is connected to a cell of internal resistance r the maximum current flows in the external resistance, when

A battery is of emt E and internal resistance r . The value of external resistance R so that the power across eternal resistance is maximum :

Tow cells with the same emf E and different internal resistances r_(1) and r_(2) are connected in series to an external resistances R . The value of R so that the potential difference across the first cell be zero is

In order to measure internal resistance r1 of a cell emf E, a meter bridge of wire resistance R_0 = 50 Omega , a resistance R_0/2 another cell of emf E/2 and galvanometer G are used in circuit. If null point is founded at l = 72cm. then value of r1

Two cell with the same e.m.f. E and difference internal resistance r_(1) and r_(2) are connected in series to an external resistance R a value of R be selected such that the potential difference as the flow cell E should be zero when