The sparking between two electrical contacts can be reduced by inserting a___________?

Related Mcqs:

1. The electric field intensity at a point situated 4 meters from a point charge is 200 N/C. If the distance is reduced to 2 meters, the field intensity will be______________?

   A. 400 N/C
   B. 600 N/C
   C. 800 N/C
   D. 1200 N/C

2. The force between two charges is 120 N. If the distance between the charges is doubled, the force will be________________?

   A. 60 N
   B. 30 N
   C. 40 N
   D. 15 N

3. Two infinite parallel plates 10 mm apart have maintained between them a potential difference of 100 V. The acceleration of an electron placed between them is______________?

   A. 0.56 x 1015 m/s2
   B. 1.5 x 1015 m/s2
   C. 1.6 x 1015 m/s2
   D. 1.76 x 1015 m/s2

4. Electric force between two point charges in air or vacuum is F. If we replace air or vacuum by an insulator (dielectric) of relative permitivity Cr the force between the charges will_______________?

   A. decrease
   B. increase
   C. remain constant
   D. depends upon composition of dielectric

5. If the distance between the two point charges become half then force between them becomes______________?

   A. double
   B. half
   C. four times
   D. remains same

6. If a third equal and similar charge is placed between two equal and similar charges, then this third charge will_____________?

   A. move out of the field of influence of the two charges
   B. remain in stable equilibrium
   C. not be in equilibrium
   D. be in unstable equilibrium

7. A positive and a negative charge are initially 50 mm apart. When they are moved close together so that they are now only 10 mm apart, the force between them will be________________?

   A. 5 times smaller than before
   B. 5 times greater than before
   C. 10 times greater than before
   D. 25 times larger than before

8. The electrostatic force between two charges of one coulomb each and placed at a distance of 0.5 m will be____________?

   A. 36 x 10fa
   B. 36 x 107 N
   C. 36 x 108 N
   D. 36 x 109 N

9. When a dielectric slab is introduced in a parallel plate capacitor, the potential difference between plates will______________?

   A. remain uncharged
   B. decrease
   C. increase
   D. become zero

10. If mica sheet is placed between the plates of a capacitor the capacity_______________?

    A. increases
    B. decreases
    C. increases then decreases
    D. decreases then increases