When the ends of conductors are kept between two points taking together the ends of conductor in an electric circuit, it is called parallel combination of resistances.
A parallel combination of 3 resistances takes a current of 7.5 A from a 30 V supply. If two resistances are 10Omega and 12 Omega , find the third resistances.
Draw a circuit diagram of an electric circuit containing a cell, a key, an ammeter, a resistor of 2 ohms in series with a combination of two resistors (4 ohms each) in parallel and a voltmeter across the parallel combination. Will the potential difference across the 2 ohms resistor be the same as that across the parallel combination of 4 ohms resistors? Give reasons.
Two metallic wires A and B of same material are connected in parallel. Wire A has length l and radius r and wire B has length 2l. Calculate the ratio of the total resistance of parallel combination and the resistance of wire A?
