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

Assertion :  The film which appears bright in reflected system will appear dark in the transmitted light and vice-versa.
Reason     : The conditions for film to appear bright or dark in reflected light are just reverse to those in the transmitted light.(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.

Unlike charges _____ each other.

The anode of a thermionic diode is connected to the negative terminal of a battery and the cathode to its positive terminal:

1. No appreciable current will pass through the diode.
2. A large current will pass through the diode from the anode to the cathode.
3. A large current will pass through the diode from the cathode to the anode.
4. The diode will be damaged.

Wires P and Q have the same resistance at ordinary (room) temperature. When heated, resistance of P  increases and that of Q decreases. We conclude that(a) P and Q are conductors of different materials(b) P is N-type semiconductor and Q is P-type semiconductor(c) P is semiconductor and Q is conductor(d) P is conductor and Q is semiconductor

In Young's double slit experiment, if monochromatic light is replaced by white light(a) All bright fringes become white(b) All bright fringes have colours between violet and red(c) Only the central fringe is white, all other fringes are coloured(d) No fringes are observed

In the valance band, the current is due to:

If an interference pattern have maximum and minimum intensities in 36 : 1 ratio then what will be the ratio of amplitudes(a) 5 : 7(b) 7 : 4(c) 4 : 7(d) 7 : 5