Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Electronic Devices question

2023 · 31 Jan · Shift 1 · Q51
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Electronic Devices
  5. /2023 · 31 Jan · Shift 1 · Q51

Electronic Devices question

2023 · 31 Jan · Shift 1 · Q51

JEE MainPhysicsElectronic DevicesMCQ+4 / −1
The effect of increase in temperature on the number of electrons in conduction band (ne\mathrm{n_e}ne​) and resistance of a semiconductor will be as:
  1. A
    ne\mathrm{n}_{\mathrm{e}}ne​ decreases, resistance increases
  2. B
    Both ne\mathrm{n}_{\mathrm{e}}ne​ and resistance increase
  3. C
    ne\mathrm{n}_{\mathrm{e}}ne​ increases, resistance decreases
  4. D
    Both ne\mathrm{n}_{\mathrm{e}}ne​ and resistance decrease
View written solutionFree

Correct answer: C

  1. Effect of temperature on a semiconductor

    In a semiconductor, when temperature increases, more valence electrons gain enough thermal energy to jump across the band gap into the conduction band.

    Therefore, the number of electrons in the conduction band nen_ene​ increases.

  2. Effect on resistance

    Resistance depends inversely on the number of charge carriers.

    Since increasing temperature produces more free electrons and holes, the conductivity increases.

    Hence, the resistance decreases.

  3. Check options

    • A: nen_ene​ decreases, resistance increases →\rightarrow→ Incorrect
    • B: Both nen_ene​ and resistance increase →\rightarrow→ Incorrect
    • C: nen_ene​ increases, resistance decreases →\rightarrow→ Correct
    • D: Both nen_ene​ and resistance decrease →\rightarrow→ Incorrect

  4. Final answer

    The correct option is C.

PreviousNext

More from Electronic Devices

  • In the given circuit, the value of current IL will be ​ mA. (When RL = 1k Ω) Includes diagram2022 · Numerical
  • In the circuit, the logical value of A=1 or B=1 when potential at A or B is 5 V and the logical value of A=0 or B=0 when potential at A or B is 0 V. The truth table of the given circuit will be : Includes diagram2022 · MCQ
  • The energy band gap of semiconducting material to produce violet (wavelength = 4000 Ao​) LED is ​eV. (Round off to the nearest integer).2022 · Numerical
  • Two ideal diodes are connected in the network as shown in figure. The equivalent resistance between A and B is ​Ω. Includes diagram2022 · Numerical
  • The photodiode is used to detect the optical signals. These diodes are preferably operated in reverse biased mode because :2022 · MCQ
  • Identify the logic operation performed by the given circuit: Includes diagram2022 · MCQ
  • In the circuit shown below, maximum zener diode current will be ​mA. Includes diagram2022 · Numerical
  • The I-V characteristics of a p-n junction diode in forward bias is shown in the figure. The ratio of dynamic resistance, corresponding to forward bias voltage of 2 V and 4 V respectively, is : Includes diagram2022 · MCQ