1. The fundamental charge or the charge of an electron is approximately:
Answer:
Explanation:
The elementary charge, commonly known as the charge of an electron or proton, is approximately 1.6 x 10^-19 Coulombs.
2. Two charges repel each other with a force F. If the distance between them is halved, the force becomes:
Answer:
Explanation:
According to Coulomb's Law, the force between two charges is inversely proportional to the square of the distance between them. If the distance is halved, the force increases by a factor of four.
3. Electric field lines never:
Answer:
Explanation:
Electric field lines never cross each other because at any point in space, an electric field has a unique direction.
4. The SI unit of electric field is:
Answer:
Explanation:
Electric field (E) is defined as the force (F) experienced by a unit positive charge (q). Therefore, its unit is Newton per Coulomb (N/C).
5. Which material does not allow charges to move freely?
Answer:
Explanation:
Insulators are materials that do not allow electric charges to move freely.
6. The electric field inside a conductor is:
Answer:
Explanation:
In electrostatic conditions, the electric field inside a conductor is zero.
7. A test charge used to measure the electric field is always:
Answer:
Explanation:
By convention, a test charge used for measuring the electric field is always positive and infinitesimally small.
8. The electric field due to a positive charge is:
Answer:
Explanation:
The electric field due to a positive charge originates or radiates outwards.
9. Electric potential is a:
Answer:
Explanation:
Electric potential is a scalar quantity as it has magnitude but no direction.
10. The work done in moving a charge in an electric field is stored as:
Answer:
Explanation:
The work done in moving a charge against an electric field is stored as its electric potential energy.
11. The electric flux through a closed surface containing no charges is:
Answer:
Explanation:
According to Gauss's law, the electric flux through a closed surface is proportional to the charge enclosed. If no charge is enclosed, the flux is zero.
12. The number of electric field lines emerging out of a positive charge is proportional to the:
Answer:
Explanation:
The number of field lines associated with a charge represents the magnitude of the charge.
13. The electric field due to an infinite plane sheet of charge is:
Answer:
Explanation:
For an infinite plane sheet of charge, the electric field remains constant and is not dependent on the distance.
14. Point charges +Q and -Q are placed at points A and B, respectively. The electric field is zero at a point:
Answer:
Explanation:
For the electric field to be zero, the point must be closer to the negative charge due to the opposing directions of the electric fields.
15. If two equal and opposite point charges are separated by a small distance, then the electric field strength between them is:
Answer:
Explanation:
Due to the close proximity and opposite nature of charges, there's a strong electric field between them.
16. Which of the following materials will allow electric charges to move most easily?
Answer:
Explanation:
Metals are good conductors of electricity and allow charges to move easily.
17. An electric dipole consists of charges of:
Answer:
Explanation:
An electric dipole consists of two charges of equal magnitude but opposite sign.
18. The torque on an electric dipole placed in a uniform electric field is:
Answer:
Explanation:
The torque on a dipole is zero when the dipole moment vector is aligned with the electric field.
19. A charged particle is placed in a uniform electric field. If the charge is doubled, the force on the particle:
Answer:
Explanation:
According to F = qE, where F is the force, q is the charge, and E is the electric field, if q is doubled, the force F also doubles.
20. The electric field intensity at a point due to a point charge is E. If the distance from the charge is doubled, the electric field intensity becomes:
Answer:
Explanation:
The electric field due to a point charge is inversely proportional to the square of the distance. Thus, doubling the distance reduces the field to a quarter of its original value.