COMEDK · Physics · 30. Semiconductors
The energy gap between valance band and the conduction band for a given material is \(6 \mathrm{~eV}\), then the material is :
- A A superconductor
- B An insulator
- C A metal
- D A semiconductor
Answer & Solution
Correct Answer
(B) An insulator
Step-by-step Solution
Detailed explanation
The electrical conductivity of a solid depends on the energy gap (\(E_g\)) between the valence band and the conduction band. Materials are classified based on the magnitude of this energy gap: 1. Metals: The valence band and conduction band overlap, or the gap is zero. 2.…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- A record player is spinning at an angular velocity of \(45 \mathrm{~rpm}\) just before it is turned off. It then decelerates at a constant rate of \(0.8 \mathrm{~rad} \mathrm{~s}^{-1}\). The angular displacement isCOMEDK 2024 Medium
- A charge of \(+1 \mathrm{C}\) is moving with velocity \(\vec{V}=(2 \mathrm{i}+2 \mathrm{j}-\mathrm{k}) \mathrm{ms}^{-1}\) through a region in which electric field \(\vec{E}=(\mathrm{i}+\mathrm{j}-3 \mathrm{k}) \quad \mathrm{NC}^{-1}\) and magnetic field \(\vec{B}=(\mathrm{i}-2 \mathrm{j}+3 \mathrm{k}) \mathrm{T}\) are present. The force experienced by the charge isCOMEDK 2024 Medium
- A sample of an ideal gas is taken through the cyclic process ABCA as shown in figure below. It absorbs 60J of heat during the part AB and rejects 80 J of heat during CA . There is no heat exchanged during the process BC . A work of 40 J is done on the gas during the part BC . If the internal energy of the gas at A is 1450 J , then the work done by the gas during the part CA is:
COMEDK 2025 Easy - An ideal gas goes from state \(A\) to state \(B\) via three different processes as indicated in the \(p-V\) diagram.
If \(Q_1, Q_2\) and \(Q_3\) indicate the heat absorbed by the three processes and \(\Delta U_1, \Delta U_2\) and \(\Delta U_3\) indicate the change in internal energy along the three processes respectively, then
COMEDK 2023 Easy - A block of a certain material is heated to a temperature of 500° C and then placed on a large ice block. If 1.455 kg of ice melts, find the mass of the block. Specific heat of the material is \(0.39\ Jg^{-1}C^{-1}\) and heat of fusion of water is \(335\ Jg^{-1}\).COMEDK 2026 Medium
- If only \(2 \%\) of the main current is to be passed through a galvanometer of resistance \(G\), then the resistance of shunt should beCOMEDK 2016 Easy
More PYQs from COMEDK
- What wilt be the density of \(\mathrm{N}_2\) gas at \(230^{\circ} \mathrm{C}\) and \(3 \mathrm{~atm}\) pressure? \(\left(R=0.082 \mathrm{~L} \mathrm{~atm} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right)\)COMEDK 2022 Easy
- Which one of the following is an example of step growth polymerisation?COMEDK 2023 Easy
- If \(\sin 3 \theta=\sin \theta\), how many solutions exist such that \(-2 \pi < \theta < 2 \pi\) ?COMEDK 2020 Medium
- In a closed vessel, 5 moles of \(A_2(g)\) and 7 moles of \(B_2(g)\) are reacted in following manner.
\(A_2(g)+3 B_2(g) \longrightarrow 2 A B_3(g)\)
What is the total number of moles of the gases present in the container at the end of the reaction?COMEDK 2024 Medium - The heat generated in a wire depends on the resistance, current and time. If the error in measuring the above are \(1 \%, 2 \%\) and \(1 \%\), respectively, the maximum error in measuring the heat isCOMEDK 2024 Easy
- A group of devices having a total power rating of 500 watt is supplied by an AC voltage \(E = 200 \sin\left(3.14t + \frac{\pi}{4}\right)\). Assuming the current in the circuit is of the form \(I = I_0 \sin(3.14t)\), the r.m.s. value of the circuit current isCOMEDK 2024 Medium