Electrostatic Potential and Capacitance Mock Test – Class 12 Physics

1. A -versus- graph for a positive point charge is used to find the radial electric field. At a given , the field magnitude is related to the graph by:

2. Assertion: A Van de Graaff generator can produce very high potential using a comparatively small amount of charge.
Reason: The dome potential is related to charge and capacitance by .

3. A notation sheet lists four symbols from electrostatic potential and capacitance. The entry that needs repair is:

4. A comparison table is made for conservative and non-conservative force ideas at a basic level. The row supported for an electrostatic force is:

5. A comparison of , , and is made for electrostatics. The supported row is:

6. The row that correctly compares potential and electric field due to a point charge is:

7. The row that correctly compares torque and potential energy of a dipole in a uniform electric field is:

8. A square has charges and at one pair of opposite corners, while the other two opposite corners are empty. At the centre of the square:

9. Two like charges are slowly pushed closer from separation to separation . The external work done in this slow process is:

10. A uniform electric field has magnitude and is directed along . If point is to the right of point , then is:

11. Three statements about a Van de Graaff generator are given.
I. Charge delivered to the dome resides on its outer surface.
II. The dome potential rises as more charge is accumulated.
III. The belt must be a good metal conductor for charge transport.

12. After a parallel-plate capacitor is charged and then disconnected from the battery, doubling the plate separation makes the potential difference between the plates:

13. A capacitor is kept connected to a battery. Its capacitance without dielectric is . After a dielectric is fully inserted, its capacitance becomes . The increase in charge on the plates is:

14. At a point , two charges produce potentials and . The net potential at is:

15. In a basic circuit idea, a capacitor is mainly introduced as a device that:

16. A negative charge moves from a point at to a point at . For this motion, the signs of and are:

17. Identify the properly classified set of quantities.

18. The row that correctly gives the voltage division for series capacitors carrying the same charge is:

19. In a parallel-plate capacitor, a dielectric slab of thickness and dielectric constant fills the full plate area but only part of the separation . The effective separation used in the capacitance formula is:

20. A student’s claim says: “If the potential at a point is zero, the electric field at that point must also be zero.” The best response is:

21. Assertion: For an isolated charged capacitor, inserting a dielectric fully reduces the stored energy.
Reason: In the isolated case, remains constant while increases.

22. A charge moves from to along Path I and returns from to along Path II in an electrostatic field. If the field does of work on the first part, the field work on the return part is:

23. On the equatorial line of a dipole, the potential is zero but the electric field is not zero. The main reason is:

24. A dipole with moment is placed in a uniform electric field . If , its potential energy is:

25. A -versus- graph for a linear capacitor is a straight line through the origin. The slope of this graph represents:

26. For a slow movement from to , the relation that correctly connects field work and potential energy is:

27. A far point on the positive axial side of a dipole has potential at distance . At a far point on the same side at distance , the potential is:

28. In the situation where a charged capacitor is connected to an identical uncharged capacitor, the final stored energy is less than the initial stored energy. The missing energy is mainly:

29. In a region, the potential is , where is in and are in . A charge moves from to . The work done by the electrostatic field is:

30. A disconnected capacitor has potential difference . A dielectric of constant is fully inserted between its plates. The new potential difference is:

31. In the previous charge-sharing type of situation, why is electrostatic energy not conserved in the final capacitor energies?

32. In a closed path in an electrostatic field, a charge returns to its starting point. The potential difference for the complete round trip is:

33. The capacitance of a conductor or capacitor is best understood as:

34. Read the situation and select the best interpretation.

What does this show about potential at a point?

35. For two large parallel plates of area , separation , and vacuum between them, the capacitance is:

36. Assertion: Inserting a dielectric fully between the plates of a parallel-plate capacitor increases its capacitance.
Reason: The dielectric reduces the effective field for the same free charge, so a smaller potential difference is produced for that charge.

37. Three charges , , and lie on a straight line at points , , and , respectively, with , , and . Taking , the total potential energy is:

38. The definition of electrostatic potential at a point would become physically unreliable if the test charge used were large because:

39. Two isolated spherical conductors in vacuum have radii and . The ratio of their capacitances is:

40. During movement from to , a charge goes from to . The work done by the electrostatic field is:

41. If a force does positive work during the displacement of a charge, the energy transfer by that force is:

42. A capacitor is disconnected after being charged to . A dielectric is fully inserted, making the capacitance . The new potential difference is:

43. The electrostatic potential energy of a charge placed at a point of potential is:

44. In the network of two parallel branches, Branch P has a single capacitor and Branch Q has in series with . The network is across . The total energy stored is:

45. A dielectric is inserted into a capacitor while the capacitor remains connected to a battery. The stored energy in the capacitor increases, although the dielectric is pulled in. The extra stored energy comes from:

46. In a series combination of two capacitors and , the voltage ratio is:

47. The energy stored in a charged capacitor can be written as:

48. In the zero-potential condition for and between the charges, . The position from is:

49. For two unlike point charges separated by , the potential energy is negative because:

50. Several capacitors are connected in parallel. The equivalent capacitance is: