23 Lecture

What is the electric field intensity at a distance of 2 meters from a point charge of 5 µC?

a) 9 x 10^9 N/C

b) 1.125 x 10^10 N/C

c) 2.25 x 10^10 N/C

d) 4.5 x 10^10 N/C

Answer: b) 1.125 x 10^10 N/C

Which law of electrostatics relates the electric field to the charge density?

a) Coulomb’s Law

b) Gauss’s Law

c) Ohm’s Law

d) Ampere’s Law

Answer: b) Gauss’s Law

What is the electric potential at a point P, located at a distance of 2 meters from a point charge of 10 µC?

a) 1.125 x 10^10 V

b) 9 x 10^9 V

c) 4.5 x 10^10 V

d) 2.25 x 10^10 V

Answer: d) 2.25 x 10^10 V

What is the potential difference between two points A and B, located at a distance of 5 cm and 10 cm respectively from a point charge of 2 µC?

a) 1.8 x 10^9 V

b) 2.2 x 10^9 V

c) 3.6 x 10^9 V

d) 4.4 x 10^9 V

Answer: c) 3.6 x 10^9 V

What is the work done in moving a charge of 5 µC from a point A to a point B, located at a distance of 10 cm and 20 cm respectively from a point charge of 10 µC?

a) -4.5 x 10^-6 J

b) 4.5 x 10^-6 J

c) 9 x 10^-6 J

d) -9 x 10^-6 J

Answer: a) -4.5 x 10^-6 J

What is the electric field intensity at the center of a circular ring of radius R and charge Q?

a) kQ/R^2

b) 2kQ/R^2

c) 3kQ/R^2

d) 4kQ/R^2

Answer: a) kQ/R^2

What is the electric field intensity at a point on the axis of a uniformly charged disc of radius R and charge Q, at a distance of x from the center of the disc?

a) kQx/2(R^2 + x^2)^(3/2)

b) kQx/(R^2 + x^2)^(3/2)

c) kQ/2(R^2 + x^2)^(3/2)

d) kQ/(R^2 + x^2)^(3/2)

Answer: b) kQx/(R^2 + x^2)^(3/2)

What is the electric potential at the center of a uniformly charged sphere of radius R and charge Q?

a) kQ/R

b) kQ/2R

c) kQ/3R

d) kQ/4R

Answer: d) kQ/4R

What is the work done in moving a charge of 10 µC from a point A to a point B, located at a distance of 5 cm and 10 cm respectively from a uniformly charged sphere

What is electric charge, and what are the two types of charges?

Answer: Electric charge is a fundamental property of matter that arises from the presence of charged particles. The two types of charges are positive and negative.

What is Coulomb's law, and how is it related to electric charges?

Answer: Coulomb's law states that the force of attraction or repulsion between two charged particles is proportional to the product of their charges and inversely proportional to the square of the distance between them. This law describes the relationship between electric charges.

What is an electric field, and how is it represented?

Answer: An electric field is a vector field that describes the force that would be exerted on a charged particle placed at any point in space. It is represented by electric field lines, which are drawn in the direction of the force on a positive test charge.

What is Gauss's law, and how is it useful in electrostatics?

Answer: Gauss's law relates the electric field to the charge distribution in space. It states that the electric flux through any closed surface is proportional to the total charge enclosed by that surface. This law is useful in calculating the electric field in various situations.

What is the potential difference, and how is it measured?

Answer: The potential difference is the amount of work done per unit charge in moving a test charge from one point to the other against the electric field. It is measured in volts (V).

What is the electric potential energy, and how is it related to the potential difference?

Answer: The electric potential energy of a charged object in an electric field is defined as the amount of work done in bringing the object from infinity to that point in the field. It is related to the potential difference by the equation ?U=q?V, where ?U is the change in electric potential energy, q is the charge, and ?V is the potential difference.

What is capacitance, and how is it related to the charge and potential difference of a capacitor?

Answer: Capacitance is the ratio of the charge on each plate of a capacitor to the potential difference between the plates. It is related to the charge and potential difference by the equation C=q/?V, where C is the capacitance, q is the charge, and ?V is the potential difference.

What is dielectric constant, and how does it affect the capacitance of a capacitor?

Answer: Dielectric constant is a measure of the ability of a material to store electrical energy in an electric field. It affects the capacitance of a capacitor by increasing it, as it reduces the electric field between the plates and allows more charge to be stored.

What is the difference between an insulator and a conductor?

Answer: An insulator is a material that does not conduct electricity, while a conductor is a material that allows electricity to flow through it.

How is the electrostatic force different from other fundamental forces of nature?

Answer: The electrostatic force is the strongest of the four fundamental forces of nature, and it has an infinite range. It is also different from the other forces because it can be both attractive and repulsive, depending on the charges involved.

Electrostatics is the study of electric charges that are at rest or not in motion. This is an important branch of physics, as electricity and magnetism are two of the fundamental forces of nature, and electrostatics is the foundation of all electric phenomena. In this article, we will discuss the basic concepts of electrostatics. Electric charge is a fundamental property of matter, which arises from the presence of charged particles such as electrons and protons. The charge on an electron is negative, and the charge on a proton is positive. The unit of charge is the Coulomb (C). The force of attraction or repulsion between two charged particles is proportional to the product of their charges and inversely proportional to the square of the distance between them. This is known as Coulomb's law. An object can be electrically charged by adding or removing electrons. If an object gains electrons, it becomes negatively charged, and if it loses electrons, it becomes positively charged. Like charges repel each other, while opposite charges attract each other. The electrostatic force between two charged particles is the strongest of the four fundamental forces, and it has an infinite range. The electric field is a vector field that describes the force that would be exerted on a charged particle placed at any point in space. The electric field is defined as the force per unit charge that a test charge would experience at that point. The electric field is represented by electric field lines, which are drawn in the direction of the force on a positive test charge. Gauss's law is a fundamental law of electrostatics that relates the electric field to the charge distribution in space. It states that the electric flux through any closed surface is proportional to the total charge enclosed by that surface. This law is useful in calculating the electric field in various situations. The potential difference between two points in an electric field is defined as the amount of work done per unit charge in moving a test charge from one point to the other against the electric field. The potential difference is measured in volts (V). The electric potential energy of a charged object in an electric field is defined as the amount of work done in bringing the object from infinity to that point in the field. The capacitance of a capacitor is defined as the ratio of the charge on each plate to the potential difference between the plates. Capacitors are used in electronic circuits for storing and releasing electric charge. They are also used in power systems for power factor correction. The dielectric constant is a measure of the ability of a material to store electrical energy in an electric field. It is defined as the ratio of the capacitance of a capacitor with the dielectric material between the plates to the capacitance of the same capacitor with a vacuum between the plates. In conclusion, electrostatics is a fundamental branch of physics that deals with the study of electric charges that are at rest or not in motion. The concepts of electric charge, electric field, potential difference, capacitance, and dielectric constant are essential for understanding various electrical phenomena. The principles of electrostatics are used in a variety of fields, including electronics, power systems, and material science.