Download App

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

Bihar BoardEnglish MediumSTD 12 SciencePhysicsSemiconductor Electronic: Material, Devices And Simple Circuits1 Mark
MCQ
A semiconductor is a material with a small but non-zero band gap that behaves as an insulator at absolute zero but allows thermal excitation of electrons into its ____________ at temperatures that are below its melting point.
  • A
    HOMO
  • B
    Valence band
  • C
    Conduction band
  • D
    LUMO
✓

Answer

  1. Conduction band

Explanation:

The band gap in case of semiconductors is of order 3−4 eV. At absolute zero, the valence band is filled and conduction band is empty, so it behaves as an insulator. As the temperature is raised, electrons in the valence band gain sufficient energy to overcome the band gap and jump to the conduction band.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q [1M]" from Semiconductor Electronic: Material, Devices And Simple Circuits→Semiconductor Electronic: Material, Devices And Simple Circuits — all question types→Physics STD 12 Science question papers→Bihar Board STD 12 Science question papers→Bihar Board question paper generator→

Similar questions

What should be the shape of a conductor that can hold a charge for long?
→

The wavelength of X-rays is of the order of

(a) Centimetre

(b) Micron (10-6 m)

(c) Angstrom (10-10 m)

(d) Metre
→
In what form is energy present in the capacitor?
→
Suppose, the electron in a hydrogen atom makes transition from n = 3 to n = 2 in 10-8s. The order of the torque acting on the electron in this period, using the relation between torque and angular momentum as discussed in the chapter on rotational mechanics is:
  1. 10-34Nm
  2. 10-24Nm
  3. 10-42Nm
  4. 10-8Nm
→
The angular resolution of a telescope of 10cm diameter at a wavelength of 5000$\mathring{\text{A}}$ is of the order of:
→
The focal length of a lens $(n=1.5)$ in air is 20 cm. Its focal length in medium of refractive index 1.5 is :
→

A 2V battery is connected across the points A and B as shown in the figure given below. Assuming that the resistance of each diode is zero in forward bias and infinity in reverse bias, the current supplied by the battery when its positive terminal is connected to A is

(a) 0.2 A

(b) 0.4 A

(c) Zero

(d) 0.1 A
→
If length of a conductor is doubled and cross-section is made half, then the specific resistance of the substance of changed wire will become:
→
On joining a battery of 50 V with a resistance of $10 \Omega$, a current of 4.5 A flows through it. The internal resistance of the battery is :
→
In a semiconductor:
  1. There are no free electrons at 0K.
  2. There are no free electrons at any temperature.
  3. The number of free electrons increases with temperature.
  4. The number of free electrons is less than that in a conductor.
→