Air gap has_________eluctance as compared to iron or steel path?

Related Mcqs:

1. What will be the magnetic potential difference across the air gap of 2 cm length in magnetic field of 200 AT/m ?

   A. 2 AT
   B. 4 AT
   C. 6 AT
   D. 10 AT

2. The initial permeability of an iron rod is________________?

   A. the highest permeability of the iron rod
   B. the lowest permeability of the iron rod
   C. the permeability at the end of the iron rod
   D. the permeability almost in non-magnetised state

3. A certain amount of current flows through a ring-shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil ?

   A. Decreases
   B. Increases
   C. Remains same
   D. First increases and then decreases depending on the depth of iron in¬sertion

4. The magnetism left in the iron after exciting field has been removed is known as____________?

   A. permeance
   B. residual magnetism
   C. susceptance
   D. reluctance

5. When an iron piece is placed in a magnetic field_____________?

   A. the magnetic lines of force will bend away from their usual paths in order to go away from the piece
   B. the magnetic lines of force will bend away from their usual paths in order to pass through the piece
   C. the magnetic field will not be affected
   D. the iron piece will break

6. Magnetising steel is normals difficult because____________?

   A. it corrodes easily
   B. it has high permeability
   C. it has high specific gravity
   D. it has low permeability

7. Hysteresis loop in case of magnetically hard materials is more in shape as compared to magnetically soft materials

   A. circular
   B. triangular
   C. rectangular
   D. none of the above

8. What will be the current passing through the ring shaped air cored coil when number of turns is 800 and ampere turns are 3200 ?

   A. 2
   B. 4
   C. 6
   D. 8

9. The materials are a bit inferior conductors of magnetic flux than air

   A. ferromagnetic
   B. paramagnetic
   C. diamagnetic
   D. dielectric

10. A square cross-sectional magnet has a pole strength of 1 x 10 Wb and cross sectional area of 20 mm x 20 mm. What is the strength at a distance of 100 mm from the unit pole in air ?

    A. 63.38 N/Wb
    B. 633.8 N/Wb
    C. 6338 N/Wb
    D. 63380 N/Wb