Electric Charges and Fields Quiz

A positive point charge Q is brought near an isolated metal cube

• The cube becomes negatively charged.

• The cube becomes positively charged.

• The interior becomes positively charged and the surface becomes negatively charged.

• The interior remains charge free and the surface gets nonuniform charge distribution.

A proton and an electron are placed in a uniform electric field.

• The electric forces acting on them will be equal.

• The magnitudes of the forces will be equal.

• Their accelerations will be equal.

• The magnitudes of their accelerations will be equal.

A point charge is brought in an electric field. The electric field at a nearby point.

• Will increase if the charge is positive.

• Will decrease if the charge is negative.

• May increase if the charge is positive.

• May decrease if the charge is negative

An electric dipole is placed in an electric field generated by a point charge.

• The net electric force on the dipole must be zero.

• The net electric force on the dipole may be zero.

• The torque on the dipole due to the field must be zero.

• The torque on the dipole due to the field may be zero.

A thin, metallic spherical shell contains a charge Q on it. A point charge q is placed at the centre of the shell and another charge q is placed outside it as shown in figure. All the three charges are positive. The force on the charge at the centre is:

• Towards left

• Towards right

• Upward

• zero

Figure shows electric field lines in which an electric dipole p is placed as shown. Which of the following statements is correct?

• The dipole will not experience any force.

• The dipole will experience a force towards right.

• The dipole will experience a force towards left.

• The dipole will experience a force upwards.

A hemisphere is uniformly charged positively. The electric field at a point on a diameter away from the centre is directed:

• Perpendicular to the diameter.

• Parallel to the diameter.

• At an angle tilted towards the diameter.

• At an angle tilted away from the diameter

Mark the correct options:

• Gauss's law is valid only for symmetrical charge distributions.

• Gauss's law is valid only for charges placed in vacuum.

• The electric field calculated by Gauss's law is the field due to the charges inside the Gaussian surface.

• The flux of the electric field through a closed surface due to all the charges is equal to the flux due to the charges enclosed by the surface.

If the net electric flux through a closed surface is zero, then we can infer:

• No net charge is enclosed by the surface.

• Uniform electric field exists within the surface.

• Electric potential varies from point to point inside the surface.

• Charge is present inside the surface.

Figure, shows some of the electric field lines corresponding to an electric field. The figure suggests that,