ECE MCQ's and doubts.

Engineering
1

To discuss questions related to various subjects of ECE. Helpful in all technical exams like gate, ies, Bsnl jto. Sail, bel, etc.

Along with this, a new feature "Concept card" is introduced to build up small concepts that would be helpful in technical interviews.

2

Bsnl jto 2009

3

Bsnl jto-2009

4

.

5


Mechanical impedance is the ratio of

  • none
  • rms force to rms velocity
  • rms velocity to rms displacement
  • rms force to rms displacement

0 voters

6



The input impedance of short-circuited line of length l where λ/4 l < λ/2, is

  • capacitive
  • resistive
  • inductive
  • none

0 voters

7

A rectangular metal waveguide filled with a dielectric of relative permittivity εr = 4, has the inside dimensions 3 x 1.2 cm, the cut off frequency for the dominant mode is

A.2.5 GHz B.5 GHz C.10 GHz D.12.5 GHz 

8


For F1 layer the maximum ionic density is 2.3 x 104 electrons per cc. The critical frequency for this layer will be

A.1.36 MHz

B.13.6 MHz

C.136 MHz

D.1360 MHz

9

The velocity of electromagnetic wave in a good conductor is

A.3 x 108 m/s

B.more than 3 x 108 m/s

C.very low

D.high

10


To increase Q factor of a coil, the wire should be

  • long and thin
  • long
  • thick
  • thin

0 voters

11



An RLC series circuit is underdamped. To make it overdamped, the value of R

  • has to be reduced to zero
  • has to be increased to infinity
  • has to be decreased
  • has to be increased

0 voters

12


The terms RMS and average values apply only to sine waves.

  • true
  • false

0 voters

13


The drift velocity of electrons is


  • D.half the speed of light
  • A.very small as compared to speed of light
  • B.equal to speed of light
  • C.almost equal to speed of light

0 voters

14

..

15

Ies 2012

16

Ies 2011

17

..

18

With increase in temperature the fermi level in an intrinsic semiconductor

  • Remains at the centre of forbidden gap
  • Moves into conduction band
  • Moves closer to valence band edge
  • Moves closer to conduction band edge

0 voters

19

Answer given in book is d..how

20

I m an student of ece. I want to ask that in barc oces will there be any questions about computer architech in ece paper?????