Electric Field and Charge Concepts

This video tutorial covers various physics problems related to electric charges, fields, and forces. It includes calculations of net charge, electric force, electric field, potential energy, and speed of electrons. The video also analyzes statements about electric concepts and explores the effects of distance and charge on electric force.

What is the net charge of a dust particle containing 5 x 10^13 protons and 8.5 x 10^13 electrons?

• 5.6 micro coulombs

• -5.6 micro coulombs

• 3.5 micro coulombs

• -3.5 micro coulombs

A negative 40 micro coulomb charge is placed 8 meters east of a 50 micro coulomb charge. What is the direction of the net electric force on the negative charge?

• South

• East

• West

• North

What is the magnitude of the electric field created by a negative 75 micro coulomb point charge at a distance of 50 cm?

• 1.5 x 10^6 N/C

• 2.7 x 10^6 N/C

• 3.5 x 10^6 N/C

• 4.2 x 10^6 N/C

What is the change in potential energy of an electron accelerated through a potential difference of 700 volts?

• -1.12 x 10^-16 J

• 1.12 x 10^-16 J

• -2.24 x 10^-16 J

• 2.24 x 10^-16 J

How much work is required to move two 50 micro coulomb charges from a distance of 500 meters to 1 meter apart?

• 0.45 J

• 0.90 J

• 1.80 J

• 1.35 J

What happens to the potential energy and work done when two like charges are brought closer together?

• Potential energy decreases, and work done is positive.

• Potential energy increases, and work done is negative.

• Potential energy remains constant, and work done is zero.

• Potential energy decreases, and work done is negative.

How is the net electric field at a point determined when multiple charges are involved?

• By adding the magnitudes of the electric fields from each charge.

• By multiplying the electric fields from each charge.

• By vectorially adding the electric fields from each charge.

• By subtracting the electric fields from each charge.

If the distance between two point charges is halved, what happens to the electric force between them?

• It remains the same.

• It halves.

• It quadruples.

• It doubles.

What is the relationship between capacitance and the separation distance in a parallel plate capacitor?

• Capacitance is directly proportional to the separation distance.

• Capacitance is proportional to the square of the separation distance.

• Capacitance is independent of the separation distance.

• Capacitance is inversely proportional to the separation distance.

Which statement is true about the electric field created by a point charge?

• It is directly proportional to the distance from the charge.

• It is directly proportional to the square of the distance from the charge.

• It is inversely proportional to the distance from the charge.

• It is inversely proportional to the square of the distance from the charge.