Profile
Settings
Refer your friends
Sign out
Electrostatics is the study of electromagnetic events that occur when no moving charges are present, i.e., when the system has reached a state of static equilibrium Because the electric force is so strong, charges quickly achieve their equilibrium locations. The distributions of the electric field and the electric potential may be calculated using electrostatic mathematical techniques using a given arrangement of charges, conductors, and insulators. In contrast, given a set of conductors with known potentials, it is feasible to estimate the charge distribution on the conductor’s surface by computing electric fields between the conductors.
1. Which of the statements below is correct?
(a) The electrostatic force is a moderate force.
(b) The effort done per unit charge in transporting a charge from any point to infinity is known as potential at a point.
(c) Electrostatic force isn’t a conservative force.
(d) The product of charge and labour is potential.
Answer- a
Explanation- As electrostatic force is not a strong force.
2. Consider an electric field that is uniform in z-direction. The potential is constant-
(a) for any x for any z
(b) for any y for any z
(c) in the x-y plane for any z
(d) for all of these.
Answer- d
3. Equipotential surfaces
(a) are closer in big electric field areas than in low electric field regions.
(b) will be more congested towards the conductor’s sharp edges.
(c) shall be evenly spaced at all times.
(d) (a) and (b) are both accurate.
Answer- d
Explanation- As these surfaces rely on area.
4. The electric field is homogeneous when-
(a) Region of constant potential
(b) There is no electric field.
(c) There will be no fee inside the area.
(d) (b) and (c) are both accurate.
Answer- d
Explanation- As electric field affects homogeneity
5. A test charge is transferred from a lower to a higher potential point. The test charge’s potential energy will-
(a) stay constant.
(b) go up
(c) go down
(d) go to zero
Answer- c
6. If a conductor has a potential V 0 and no other charges outside, then-
(a) there must be charges on the surface or within the conductor.
(b) There can’t be any charge in the conductor’s body.
(c) Charges must only exist on the surface.
(d) (a) and (b) are both accurate.
Answer- c
Explanation- As only a conductor can hold charge in such a case.
7. Which of the following assertions about a perfect conductor is incorrect?
(a) The conductor’s surface is an equal-area surface.
(b) The electric field immediately outside a conductor’s surface is perpendicular to it.
(c) The charge carried by a conductor is always evenly distributed throughout the conductor’s surface.
(d) None of the preceding.
Answer- b
8. The maximum force of attraction between two charges separated by a distance-
(a) grows K times
(b) stays steady
(c) drops K times
(d) increases K-1 times when air is replaced by a dielectric medium of constant K.
Answer- c
Explanation- As attraction is dependent on K
9. When the area of a parallel plate capacitor is reduced-
(a)the capacity rises.
(b) the gap between the plates widens.
(c) the plate’s surface area is enlarged.
(d) The dielectric constant is always decreasing.
Answer- c
10. A V volt potential differential is applied to a parallel plate air capacitor. After removing the charging battery, an insulating handle is used to increase the space between the capacitor’s plates. As a consequence, the potential difference between the plates –
(a) rises
(b) falls
(c) remains constant
(d) falls to zero.
Answer- a
Explanation- As the insulator is insulation in the charges, so, V is dropping.
11. Two identical capacitors are connected in parallel, charged to a potential of V, then separated and connected in series, with the positive plate of one linked to the negative plate of the other. Which of the following statements is correct?
(a) The charges on the unconnected free plated are annihilated.
(b) The amount of energy stored in the system grows.
(c) The difference in potential between the free plates is 2V.
(d) The potential difference is unaffected.
Answer- c
Explanation- As total V is calculated by the addition of all V present.
12. A capacitor is linked to a dc source and contains some dielectric between its plates. After disconnecting the battery and removing the dielectric-
(a) the capacitance will rise.
(b) the amount of energy stored will decrease.
(c) the electric field will expand.
(d) The voltage will drop.
Answer- c
13. In a homogeneous electric field, a positively charged particle is liberated from rest. Because the electric field is uniform, the charge-
(a)(electric)’s potential energy stays constant.
(b)Because the charge flows along the electric field rises.
(c)Because the charge flowing along the electric field decreases.
(d)Because the charge flowing in the opposite direction of the electric field decreases.
Answer- c
14. A battery is used to charge a capacitor, which is then detached. The plates were subsequently separated by a dielectric slab, which resulted in-
(a) a drop in charge on the plates and a rise in the potential difference across the plates.
(b) a rise in the potential difference across the plate, a decrease in stored energy, but no change in plate charge
(c) a decrease in the potential difference between the plates, a drop in stored energy, but no change in the charge on the plates.
(d) none of the preceding
Answer- c
Explanation: – As it depends on stored charge, so, V is dropping.
15. When a unit positive charge is transferred from one point to another over an equipotential surface, the charge undergoes-
(a) work.
(b) the charge is in charge of the task.
(c) the amount of work done is constant.
(d) no work has been completed.
Answer- d
Explanation- (d) Because the electric field on the equipotential surface is normal to the charged surface (where potential exists), no work is done.
16. A hollow metal sphere with a radius of 5 cm is charged to a potential of 10 V on its surface. The potential at the sphere’s centre is-
(a) 0 V
(b) 10 V
(c) Same as at a distance of 5 cm from the surface (e) Same as at a distance of 25 cm from the surface
Answer- b
