Questions in Current Electricity

Select	Question
	A resistance R is stretched to four times its length. Its new resistance will be
	What is the resistance of a carbon resistance which has bands of colours brown, black and brown
	The lead wires should have
	The alloys constantan and manganin are used to make standard resistance due to they have
	When a potential difference is applied across the ends of a linear metallic conductor
	The electric resistance of a certain wire of iron is R. If its length and radius are both doubled, then
	A wire of diameter 0.02 metre contains $10^{28}$ free electrons per cubic metre. For an electrical current of 100 A, the drift velocity of the free electrons in the wire is nearly
	The following four wires are made of the same material and are at the same temperature. Which one of them has highest electrical resistance
	The colour sequence in a carbon resistor is red, brown, orange and silver. The resistance of the resistor is
	A thick wire is stretched so that its length become two times. Assuming that there is no change in its density, then what is the ratio of change in resistance of wire to the initial resistance of wire