MCQ
Unit of relative permeability is:
- Aweber/m
- ✓without unit
- Chenry/m
- Dampere/m
✓
Answer
Correct option: B.
without unit
(b) without unit
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
The strength of the magnetic field in which the magnet of a vibration magnetometer is oscillating is increased 4 times its original value. The frequency of oscillation would then become
| (a) Twice its original value | (b) Four times its original value |
| (c) Half its original value | (d) One-fourth its original value |
Assertion : Diamond glitters brilliantly.
Reason : Diamond does not absorb sunlight.
|
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |
In a PN-junction diode
|
(a) The current in the reverse biased condition is generally very small |
|
(b) The current in the reverse biased condition is small but the forward biased current is independent of the bias voltage |
|
(c) The reverse biased current is strongly dependent on the applied bias voltage |
|
(d) The forward biased current is very small in comparison to reverse biased current |
In the middle of the depletion layer of a reverse-biased PN junction, the
|
(a) Potential is zero |
(b) Electric field is zero |
|
(c) Potential is maximum |
(d) Electric field is maximum |
Excitation energy of a hydrogen like ion in its first excitation state is 40.8 eV. Energy needed to remove the electron from the ion in ground state is
| (a) 54.4 eV | (b) 13.6 eV | (c) 40.8 eV | (d) 27.2 eV |
In an NPN transistor circuit, the collector current is 10 mA. If 90% of the electrons emitted reach the collector, the emitter current (iE) and base current (iB) are given by
|
(a) iE = – 1 mA, iB = 9 mA |
(b) iE = 9 mA, iB = – 1 mA |
|
(c) iE = 1 mA, iB = 11 mA |
(d) iE = 11 mA, iB = 1 mA |
A solid sphere and a hollow sphere of the same material and of equal radii are heated to the same temperature:
→- Both will emit equal amount of radiation per unit time in the biginning.
- Both will absorb equal amount of radiation from the surrounding in the biginning.
- The initial rate of cooling $\Big(\frac{\text{dT}}{\text{dt}}\Big)$ will be the same for the two spheres.
- The two spheres will have equal temperatures at any instant.
Select the right option in the following
|
(a) Christian Huygens a contemporary of Newton established the wave theory of light by assuming that light waves were transverse |
|
(b) Maxwell provided the compelling theoretical evidence that light is transverse wave |
|
(c) Thomas Young experimentally proved the wave behaviour of light and Huygens assumption |
|
(d) All the statements give above, correctly answers the question “what is light” |
What is the momentum of a photon having frequency 1.5 
|
(a) 3.3 |
(b) 3.3 |
|
(c) 6.6 |
(d) 6.6 |
When a piece of a ferromagnetic substance is put in a uniform magnetic field, the flux density inside it is four times the flux density away from the piece. The magnetic permeability of the material is
|
(a) 1 |
(b) 2 |
(c) 3 |
(d) 4 |