Two inductors each of inductance L are connected in parallel. What is their equivalent inductance?
2L
L
L/2
L/4
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
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
An electirc kettle boils 1 kg of water in time t1 and another kettle boils the same amount of water in time t2. When they are joined in series, the time required to boil 1 kg of water is
t1 + t2
Kirchhoff's current law at a junction deals with conservation of
charge
energy
momentum
all of these
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
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
The resistor R1 dissipates power P, when connected to a generator. If a resistor R2 is inserted in series with R1, the power dissipated by R1
may increase or decrease depending on the value fo R1 and R2
