Class 12 Electrostatic Potential And Capacitance CBSE Questions & Answers

Class 12 · Electrostatic Potential And Capacitance

This is Physics Class 12 Electrostatic Potential and Capacitance CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Work done by a uniform electric field E in moving a charge q a distance d from a to b is
  • A
    \({\rm{qE}}/{\rm{d}}\)
  • B
    \({\rm{qE}}/{{\rm{d}}^{\rm{2}}}\)
  • C
    qEd
    Correct
  • D
    \({\rm{q}}/\left( {{\rm{Ed}}} \right)\)
2
Electric potential energy of two point charges q and \({{\rm{q}}_0}\) is
  • A
    \(\frac{1}{4\pi\epsilon_0} \frac{qq_0}{r}\)
    Correct
  • B
    \(\frac{1}{4\pi\epsilon_0} \frac{qq_0}{r^3}\)
  • C
    \(\frac{1}{4\pi\epsilon_0} \frac{q^2q_0}{r}\)
  • D
    \(\frac{1}{4\pi\epsilon_0} \frac{qq_0}{r^2}\)
3
If a charge moves in an electrical field
  • A
    energy is gained
  • B
    energy is unchanged
  • C
    energy is lost
  • D
    energy is conserved
    Correct
4
If a charge \({{\rm{q}}_0}\) is there in a field caused by several point charges \({{\rm{q}}_i}\) The potential energy of \({{\rm{q}}_0}\) is given by
  • A
    \(\frac{1}{2\pi\epsilon_0} \Sigma\frac{q_iq_0}{r}\)
  • B
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_iq_0}{r^3}\)
  • C
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_iq_0}{r}\)
    Correct
  • D
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_iq_0}{r^2}\)
5
Electric Potential V at a point in an electrical field is
  • A
    potential energy of all charges in the field.
  • B
    potential energy of a proton placed at that point.
  • C
    potential energy of a unit charge placed at that point.
    Correct
  • D
    potential energy of an electron placed at that point.
6
In circuits, a difference in potential from one point to another is often called
  • A
    voltage
    Correct
  • B
    AT
  • C
    volts
  • D
    field
7
If a positive charge moves in the direction of the electric field
  • A
    Field does positive work on charge,potential energy decreases
    Correct
  • B
    Field does positive work on charge,potential energy increases
  • C
    Field does negative work on charge,potential energy increases
  • D
    Field does negative work on charge,potential energy decreases
8
If a positive charge moves opposite to the direction of the electric field
  • A
    Field does negative work on charge,potential energy increases
    Correct
  • B
    Field does positive work on charge,potential energy increases
  • C
    Field does positive work on charge,potential energy decreases
  • D
    Field does negative work on charge,potential energy decreases
9
Electric Potential is
  • A
    potential energy per unit volume
  • B
    potential energy of the field
  • C
    potential energy of all charges
  • D
    potential energy per unit charge
    Correct
10
The unit of potential difference as used in electrical circuits is
  • A
    joule
  • B
    volt
    Correct
  • C
    electron volt
  • D
    coulomb
11
electric potential at a distance r from a point charges q is
  • A
    \(\frac{1}{4\pi\epsilon_0} \frac{q^2}{r}\)
  • B
    \(\frac{1}{4\pi\epsilon_0} \frac{q}{r^3}\)
  • C
    \(\frac{1}{4\pi\epsilon_0} \frac{q}{r}\)
    Correct
  • D
    \(\frac{1}{4\pi\epsilon_0} \frac{q}{r^2}\)
12
In a system of n point charges electric potential at a point P having a distance \({{\rm{r}}_{\rm{i}}}\) from the charge \({{\rm{q}}_{\rm{i}}}\) is
  • A
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_i}{r}\)
    Correct
  • B
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_i}{r^3}\)
  • C
    \(\frac{1}{4\pi\epsilon_0} \Sigma\frac{q_i}{r^2}\)
  • D
    \(\frac{1}{2\pi\epsilon_0} \Sigma\frac{q_i}{r}\)
13
For a one dimensional electric field the correct relation of \(\vec{E}\) and potential V is
  • A
    \(-\frac{d^2V}{dx^2}\)
  • B
    \(\frac{d^2V}{dx^2}\)
  • C
    \(\frac{dV}{dx}\)
  • D
    \(-\frac{dV}{dx}\)
    Correct
14
Electric-field magnitude E at points inside and outside a positively charged spherical conductor having charge Q and a radius R are
  • A
    less than 0,\(\frac{1}{4\pi\epsilon_0} \frac{Q}{R^2}\)
  • B
    greater than 0,\(\frac{1}{4\pi\epsilon_0} \frac{Q}{R^2}\)
  • C
    0, \(\frac{1}{4\pi\epsilon_0} \frac{Q}{R}\)
    Correct
  • D
    \(\frac{1}{4\pi\epsilon_0} \frac{Q}{R^2}\)
15
If R is the radius of a spherical conductor, \({{\rm{V}}_{\rm{m}}}\) the dielectric strength, maximum electric-field magnitude to which it can be raised is
  • A
    \({{\rm{V}}_{\rm{m}}}/{{\rm{R}}^{\rm{2}}}\)
  • B
    \({{\rm{V}}_{\rm{m}}}^{\rm{2}}/{{\rm{R}}^{\rm{2}}}\)
  • C
    \({{\rm{V}}_{\rm{m}}}^{\rm{2}}/{\rm{R}}\)
  • D
    \({{\rm{V}}_{\rm{m}}}/{\rm{R}}\)
    Correct