MCQ
In semiconductors, at a room temperature:
  • The valence band is partially empty and the conduction band is partially filled.
  • B
    The valence band is completely filled and the conduction band is partially filled.
  • C
    The valence band is completely filled.
  • D
    The conduction band is completely empty.

Answer

Correct option: A.
The valence band is partially empty and the conduction band is partially filled.

In semiconductors at room temperature the electrons get enough energy so that they are able to over come the forbidden gap. Thus at room temperature the valence band is partially empty and conduction band is partially filled.

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

Similar questions

A conducting ring is placed around the core of an electromagnet as shown in fig. When key K is pressed, the ring
An electron enters the space between the plates of a charged capacitor as shown. The charge density on the plate is $\sigma $. Electric intensity in the space between the plates is $E$. A uniform magnetic field $B$ also exists in that space perpendicular to the direction of $E$. The electron moves perpendicular to both $\vec E$ and $\vec B$ without any change in direction. The time taken by the electron to travel a distance $\ell $ is the space is
When a photon stimulates the emission of another photon, the two photons have:
Which of the following statement regarding transformer is incorrect?
The focal length of a planoconvex glass lens is $20 \,cm \left(\mu_g=1.5\right)$. The plane face of it is silvered. An illuminating object is placed at a distance of $60 cm$ from the lens on its axis along the convex side. Then the distance (in $cm$ ) of the image is .........
A wave is represented by the equation $-\text{y}=(0.001\text{mm})\sin\Big[(50\text{s}^{-1})\text{t}+(2.0\text{m}^{-1})\text{x}\Big]$
  1. The wave velocity $= 100m/s.$
  2. The wavelength $= 2.0m.$
  3. The frequency $=\frac{25}{\pi}\text{Hz}$
  4. The amplitude $= 0.001mm.$
In AM, the centpercent modulation is achieved when
Two concave lenses $L_1$ and $L_2$ are kept in contact with each other. If the space between the two lenses is filled with a material of refractive index $\mu\approx1,$ the magnitude of the focal length of the combination:
Circular region of radius $R$ has uniform magnetic field $B = {B_0} + {B_0}t\left( { - \hat k} \right).\,At\,\,t\, = 0\,$ acceleration of charged particle 
The light rays having photons of energy $1.8 eV$ are falling on a metal surface having a work function $1.2 eV$. What is the stopping potential to be applied to stop the emitting electrons .......... $eV$