A battery of 24 cells each of emf 1.5 V and internal resistance $2\Omega$ is connected so as to send maximum current through a 12 resistance. In order to achieve this we must connect.

2 rows of 12 cells connected in parallel

6 cells in series and connect 4 such rows in parallel

2 rows of 12 cells connected in parallel

Which of the following statement is correct?

For semi conductors resistivity becomes very large at low temperatures tending to infinitely large values as. $T\longrightarrow 0$

For metals, resistivity increases linearly with temperature, at all temperatures.

For insulators, resistivity decreases exponentially with decreasing temperatures.

For semi conductors resistivity becomes very large at low temperatures tending to infinitely large values as. $T\longrightarrow 0$

Resistivity increases with temperatures for metals, insulators as well as semiconductors.

2 rows of 12 cells connected in parallel

For semi conductors resistivity becomes very large at low temperatures tending to infinitely large values as. $T\longrightarrow 0$

A battery of 24 cells each of emf 1.5 V and internal resistance $2\Omega$ is connected so as to send maximum current through a 12 resistance. In order to achieve this we must connect.

The mean free path of electrons in a metal is $4 \times 10 ^{-8}\,m.$ The electric field which can give on an average 2eV energy to an electron in the metal will be in the units V/m.

The length of a wire is doubled and current through it is increased by a factor of $\frac32$ without any change of temperature. The resistivity of the material of the wire

A copper wire is stretched to make it 0.1% longer. Then the percentage change in its resistance is

To obtain the optimum sensitivity of a Wheatstone bridge, for a given ‘want of balance’, and with a freedom of choice of arrangement, we should.

Two wires, made of tinned copper, having identical cross section and different lengths, are used as fuses. Then

A fuse, with a radius of 0.1 mm blows at 10A. What should be the radius of fuse wire made of the same material which melts at 20A?

A piece of silver and another of germanium cooled from room temperature to 85K. Then the resistance of