Current Electricity

In a meter bridge experiment to determine the value of unknown resistance, first the resistances 2 and 3 are connected in the left and right gaps of the bridge and the null point is obtained at a distance l cm from the left. Now when an unknown resistance x is connected in parallel to 3 resistance, the null point is shifted by 10 cm to the right of wire. The value of unknown resistance x is .

The heat generated in 1 minute between points A and B in the given circuit, when a battery of 9 V with internal resistance of 1 is connected across these points is J. [figure]

The value of current I in the electrical circuit as given below, when potential at A is equal to the potential at B, will be A. [figure]