A semiconductor -resistor is connected in parallel with a variable resistance.This combination is joined in series with an electric cell and a milliammeter . If the temperature increases,how would you keep the milliammeter reading to a constant value? Justify your answer.

A parallel combination of three resistances of 6 Omega, 12 Omega and 12 Omega is connected in series with an electric cell of emf 1.5 V and internal resistance 2 Omega . Find out the currents through the three resistances.

For n number of resistors of magnitude r connected in parallel, the equivalent resistance in R. What will be the value of the equivalent resistance when they are connected in series? Or, show that if n identical conductors are joined in series, the combined resistance is n^2 times as great as when they are joined in parallel.

5 Identical cells are connected in series to form a row, 3 such rows are connected in parallel to form a combination of cells. The combination sends 1A current through an external resistance of 9 Omega . But if the resistance of the external circuit be 19 Omega then the currents is reduced to half of its previous value. Determine the em and internal resistance of each coil.

The emf of a dry cell is 1.5 V , when an ammeter and a resistance are connected with the series combination of two dry cells in series,then the ammeter reads 1A,and when the cells are connected in parallel the reading of the ammeter becomes 0.75A What is the internal resistance of the dry cell? Draw the circuit diagrams?

A conductor in series with an ammeter and a semiconductor in series with another ammeter are connected in parallel. At a certain voltage both the ammeters register the same current. Will this condition remains as such if the voltage of the dc source is increased? Explain your answer.

An electric cell of emf 10 V and of internal resistance 1 Omega is connected in series with the parallel combination of three resistances of 3 Omega,5 Omega and 8 Omega .Calculate the currents through the three resistances.

you have several identical electric cells. IF the internal resistance of the cells be (i) very much greater (ii) very much smaller than external resistance, then how should the cells be connected with that resistance to increase the current through it?