Unit I: Electrostatics - Online Test
Q1. Two identical point charges
of magnitude –q are fixed as shown in the figure below. A third charge +q is
placed midway between the two charges at the point P. Suppose this charge +q is
displaced a small distance from the point P in the directions indicated by the
arrows, in which direction(s) will +q be stable with respect to the
displacement?
Answer : Option B
Explaination / Solution:
Hint: Since V=0 along equatorial line
Q2. Which charge configuration
produces a uniform electric field?
Answer : Option C
Explaination / Solution:
No Explaination.
Q3. What is the ratio of the
charges |q1/q2| for the following electric field line pattern?
Answer : Option D
Explaination / Solution:
Q4. An electric dipole is
placed at an alignment angle of 30º with an electric field of 2 × 105
N C-1. It experiences a torque equal to 8 N m. The charge on the
dipole if the dipole length is 1 cm is
Answer : Option B
Explaination / Solution:
Q5. Four Gaussian surfaces are
given below with charges inside each Gaussian surface. Rank the electric flux
through each Gaussian surface in increasing order.
Answer : Option A
Explaination / Solution:
Q6. The total electric flux for
the following closed surface which is kept inside water
Answer : Option B
Explaination / Solution:
Q7. Two identical conducting
balls having positive charges q1 and q2 are separated by
a center to center distance r. If they are made to touch each other and then
separated to the same distance, the force between them will be
Answer : Option C
Explaination / Solution:
Q8. Rank the electrostatic
potential energies for the given system of charges in increasing order.
Answer : Option A
Explaination / Solution:
Q9. An electric field 
exists in a certain region
of space. Then the potential difference V = Vo – VA,
where Vo is the potential at the origin and VA is the
potential at x = 2 m is:
exists in a certain region
of space. Then the potential difference V = Vo – VA,
where Vo is the potential at the origin and VA is the
potential at x = 2 m is:
Answer : Option B
Explaination / Solution:
Q10. A thin conducting spherical
shell of radius R has a charge Q which is uniformly distributed on its surface.
The correct plot for electrostatic potential due to this spherical shell is
Answer : Option B
Explaination / Solution:
No Explaination.
