Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

The work function for photoelectric effect:

Two coherent sources of light can be obtained by(a) Two different lamps(b) Two different lamps but of the same power(c) Two different lamps of same power and having the same colour(d) None of the above

For a common base amplifier, the values of resistance gain and voltage gain are 3000 and 2800 respectively. The current gain will be:

The excess pressure inside a soap bubble is twice the excess pressure inside a second soap bubble. The volume of the first bubble is n times the volume of the second where n is:

1. 4
2. 2
3. 1
4. 0.125.

Which of the following transition will have highest emission wavelength(a) n = 2 to  n = 1 (b) n = 1 to n = 2 (c) n = 2 to n= 5 (d) n = 5 to n = 2

A ferromagnetic material is placed in an external magnetic field. The magnetic domains:

A particle is fastened at the end of a string and is whirled in a vertical circle with the other end of the string being fixed. The motion of the particle is:

1. Periodic.
2. Oscillatory.
3. Simple harmonic.
4. Angular simple harmonic.

 When is the conduction current the same as the displacement current?

Assertion  :  Zener diode works on a principle of breakdown voltage.
Reason      : Current increases suddenly after breakdown voltage.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.