Electrostatics deals with the study of forces, fields, and potential arising from static charges. Which of the following statements are correct? Choose the correct answer from the options given below:
(A), (C), and (D) only
The correct statements are:
- (A) Electrostatic force is a conservative force, meaning the work done by the electrostatic force in moving a charge between two points depends only on the initial and final positions and not on the path taken.
- (C) In a uniform electric field, an electric dipole experiences a torque but no net force, because the forces on its two opposite charges cancel out.
- (D) Electric field lines start from positive charges and end at negative charges. If an isolated charge exists, field lines may start or end at infinity.
Statement (B) is also correct since charge is quantized in integral multiples of the electron’s charge.
Thus, the correct answer is (b) (A), (C), and (D) only.
Important Questions from Electric Charges and Fields
Two charged particles, placed at a distance d apart in vacuum, exert a force F on each other. Now, each of the charges is doubled. To keep the force unchanged, the distance between the charges should be changed to:
When a slab of insulating material 4 mm thick is introduced between the plates of a parallel plate capacitor of separation 4 mm, it is found that the distance between the plates has to be increased by 3.2 mm to restore the capacity to its original value. The dielectric constant of the material is:
Match List - I with List - II.
List - I List - II (A) Electric Field (I) [LTA] (B) Electric Flux (II) [L2] (C) Electric Dipole Moment (III) [ML3T−3A−1] (D) Area Vector Element (IV) [MLT−3A−1] Choose the correct answer from the options given below:
A thin metallic spherical shell contains a charge +10 μC on it. A point charge +2 μC is placed at the centre of the shell and another charge +5 μC is placed outside it as shown. The force on the charge +2 μC at the centre is:
In the figure, an α-particle moves a distance l in a uniform electric field E as shown. Does the Electric Field do a positive or a negative work on the α-particle? Does the electric potential energy of the α-particle increase or decrease?
