ELECTROSTATICS
1. What is the SI unit of electric charge?
a) Ampere
b) Coulomb
c) Volt
d) Ohm
2. Coulomb's law gives the force between two charged objects as a function of their:
a) Electric fields
b) Magnetic fields
c) Masses
d) Charges
3. The electric field at a point is defined as the:
a) Force per unit charge experienced by a test charge placed at that point
b) Distance between two charges
c) Potential difference between two points
d) Rate of flow of electric current
4. The intensity of the electric field is directly proportional to the:
a) Electric potential at that point
b) Magnitude of the charge creating the field
c) Distance from the charge creating the field
d) Electric flux through a closed surface
5. Electric lines of force:
a) Always form closed loops
b) Are always parallel to each other
c) Indicate the direction of the electric field
d) Are always perpendicular to the electric field
6. Electric flux passing through a closed surface depends on:
a) The magnitude of the charge enclosed by the surface
b) The shape of the surface
c) The distance of the surface from the charge
d) All of the above
7. Gauss's law relates the electric flux through a closed surface to the:
a) Electric field at the surface
b) Charge enclosed by the surface
c) Distance from the charge to the surface
d) Electric potential at the surface
8. The application of Gauss's law is most useful in calculating the electric field for:
a) Point charges
b) Charges distributed symmetrically
c) Non-uniformly charged objects
d) Moving charges
9. Electric potential at a point is defined as the:
a) Work done in moving a unit positive charge from infinity to that point
b) Force per unit charge experienced by a test charge at that point
c) Ratio of electric field to the distance from the point
d) Magnitude of the charge at that point
10. The absolute potential at a point is always measured:
a) With respect to the Earth's surface
b) With respect to a fixed reference point
c) With respect to the magnetic field
d) With respect to the temperature at that point
11. The electric potential near an isolated point charge decreases with:
a) Decreasing distance from the charge
b) Increasing distance from the charge
c) The square of the distance from the charge
d) The cube of the distance from the charge
12. The relation between electric field and electric potential is given by:
a) E = V/d
b) V = Ed
c) E = Vd
d) V = E/d
13. The electron volt (eV) is a unit of:
a) Electric charge
b) Electric potential
c) Electric current
d) Energy
14. Equipotential surfaces in an electric field are:
a) Always parallel to each other
b) Always perpendicular to each other
c) Concentric spheres around the charge
d) Straight lines passing through the charge
15. Capacitance is a measure of:
a) The charge stored on a capacitor
b) The potential difference across a capacitor
c) The ability of a capacitor to store charge
d) The time constant of a circuit
16. The capacitance of a parallel plate capacitor depends on:
a) The area of the plates
b) The distance between the plates
c) The dielectric material between the plates
d) All of the above
17. When a dielectric material is inserted between the plates of a capacitor, the capacitance:
a) Decreases
b) Increases
c) Remains unchanged
d) Depends on the temperature
18. In a parallel combination of capacitors, the total capacitance is:
a) The sum of the individual capacitances
b) The product of the individual capacitances
c) The reciprocal of the sum of the individual capacitances
d) The reciprocal of the product of the individual capacitances
19. In a series combination of capacitors, the total capacitance is:
a) The sum of the individual capacitances
b) The product of the individual capacitances
c) The reciprocal of the sum of the individual capacitances
d) The reciprocal of the product of the individual capacitances
20. The potential difference across a capacitor is directly proportional to:
a) The charge stored on the capacitor
b) The electric field between the plates
c) The area of the plates
d) The distance between the plates
21. The electric field between the plates of a parallel plate capacitor is:
a) Uniform
b) Non-uniform
c) Zero
d) Infinite
22. The charge stored on a capacitor is directly proportional to:
a) The voltage across the capacitor
b) The electric field between the plates
c) The area of the plates
d) The distance between the plates
23. A capacitor is fully charged when:
a) The voltage across it is zero
b) The charge stored on it is zero
c) The electric field between the plates is zero
d) The capacitance is maximum
24. A dielectric material between the plates of a capacitor:
a) Increases the capacitance
b) Decreases the capacitance
c) Does not affect the capacitance
d) Turns the capacitor into a resistor
25. The electric field inside a capacitor with a dielectric material is:
a) Greater than the electric field without the dielectric
b) Less than the electric field without the dielectric
c) The same as the electric field without the dielectric
d) Zero
26. The potential difference between two equipotential surfaces is:
a) Constant
b) Increasing
c) Decreasing
d) Zero
27. The work done in moving a positive charge along an equipotential surface is:
a) Zero
b) Non-zero
c) Negative
d) Positive
28. The capacitance of a spherical capacitor depends on:
a) The radius of the inner sphere
b) The radius of the outer sphere
c) The distance between the spheres
d) All of the above
29. The capacitance of a cylindrical capacitor depends on:
a) The length of the cylinder
b) The radius of the inner cylinder
c) The radius of the outer cylinder
d) All of the above
30. The total capacitance of a combination of capacitors in series is always:
a) Greater than the capacitance of any individual capacitor
b) Less than the capacitance of any individual capacitor
c) Equal to the capacitance of any individual capacitor
d) Zero
31. The total capacitance of a combination of capacitors in parallel is always:
a) Greater than the capacitance of any individual capacitor
b) Less than the capacitance of any individual capacitor
c) Equal to the capacitance of any individual capacitor
d) Zero
32. A capacitor is used to store:
a) Electric charge
b) Magnetic field
c) Heat energy
d) Mechanical energy
33. The charge stored on a capacitor can be increased by:
a) Increasing the voltage across it
b) Decreasing the voltage across it
c) Changing the dielectric material between the plates
d) None of the above
34. The charge stored on a capacitor can be decreased by:
a) Increasing the voltage across it
b) Decreasing the voltage across it
c) Changing the dielectric material between the plates
d) None of the above
35. The unit of capacitance is:
a) Ohm
b) Ampere
c) Farad
d) Joule
36. The unit of electric potential is:
a) Volt
b) Ampere
c) Ohm
d) Joule
37. The unit of electric field intensity is:
a) Volt
b) Ampere
c) Ohm
d) Newton/Coulomb
38. The unit of electric flux is:
a) Newton
b) Ampere
c) Coulomb
d) Volt
39. The unit of electric charge is:
a) Coulomb
b) Ampere
c) Ohm
d) Farad
40. The unit of electric current is:
a) Ampere
b) Coulomb
c) Ohm
d) Farad
41. The unit of resistance is:
a) Ohm
b) Ampere
c) Volt
d) Farad
42. The unit of energy is:
a) Joule
b) Ampere
c) Ohm
d) Coulomb
43. The unit of power is:
a) Watt
b) Ampere
c) Volt
d) Ohm
44. The unit of work is:
a) Joule
b) Ampere
c) Volt
d) Coulomb
45. The unit of electric potential difference is:
a) Volt
b) Ampere
c) Ohm
d) Joule
46. The unit of electric field strength is:
a) Newton/Coulomb
b) Ampere
c) Volt
d) Ohm
47. The unit of electric flux density is:
a) Coulomb
b) Ampere
c) Volt
d) Farad
ANSWER KEY:
- b) Coulomb
- d) Charges
- a) Force per unit charge experienced by a test charge placed at that point
- b) Magnitude of the charge creating the field
- c) Indicate the direction of the electric field
- d) All of the above
- b) Charge enclosed by the surface
- b) Charges distributed symmetrically
- a) Work done in moving a unit positive charge from infinity to that point
- b) With respect to a fixed reference point
- a) Decreasing distance from the charge
- b) V = E*d
- d) Energy
- c) Concentric spheres around the charge
- c) The ability of a capacitor to store charge
- d) All of the above
- b) Increases
- c) The reciprocal of the sum of the individual capacitances
- a) The sum of the individual capacitances
- a) The charge stored on the capacitor
- a) Uniform
- a) The voltage across the capacitor
- b) The charge stored on it is zero
- a) Increases the capacitance
- b) Less than the electric field without the dielectric
- a) Constant
- a) Zero
- d) All of the above
- d) All of the above
- b) Less than the capacitance of any individual capacitor
- a) Greater than the capacitance of any individual capacitor
- a) Electric charge
- a) Increasing the voltage across it
- b) Decreasing the voltage across it
- c) Farad
- a) Volt
- d) Newton/Coulomb
- c) Coulomb
- a) Coulomb
- a) Ampere
- a) Ohm
- a) Joule
- a) Watt
- a) Joule
- a) Volt
- a) Newton/Coulomb
- c) Volt
