A piece of copper and another of germanium are cooled from room temperature to 80K.The resistance of
each of them increases
each of them decreases
copper increases and germanium decreases
copper decreases and germanium increases
Two inductors each of inductance L are connected in parallel. What is their equivalent inductance?
2L
L
L/2
L/4
Iron and silicon wires are heated from 30°C to 50°C.The correct statement is that
resistance of both the wires increases
resistance of both the wires decreases
resistance of iron wire increases and that of silicon wire decreases
resistance of iron wire decreases and that of silicon wire increases
The length of a potentiometer wire is 5 metres. An electron in this wire experiences a force of 4.8 × 10-19 newton, emf of the main cell used in potentiometer is
3 volt
15 volt
1.5 volt
5 volt
In a potentiometer of 10 wires,the balance point is obtained on the 7th wire.To shift the balance point to 9th wire,we should
decrease resistance in the main circuit
increase resistance in the main circuit
decrease resistance in series with the cell whose emf is to be measured
increase resistance in series with the cell whose emf is to be determined
The negative Zn pole of a Daniell cell, sending a contant current through a circuit, decreases in mass by 0.13 g in 30 minutes. If the electrochemical equivalent of Zn and Cu are 32.5 and 31.5 respectively, the increase in the mass of the positive Cu pole in this time is
0.180 g
A condenser having a capacity of 2 μF is charged to 200 V and then the plates of the capacitor are connected to a resistance wire.The heat produced is
2 x 10-2 J
4 x 10-2 J
4 x 10-4 J
4 x 1010 J
In a potentiometer of 10 wires, the balance point is obtained on the 7th wire. To shift the balance point to 9th wire, we should
increase resistance in series with circuit
increase resistance in series with the cell whose emf is to be determine