Force on Moving Charge

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What is the force experienced by a moving charge in a magnetic field?

The force is called the Lorentz force and is given by F = q(v × B).

What are the factors that influence the magnitude of force on a moving charge?

The magnitude is influenced by the charge magnitude, velocity of the charge, and the strength of the magnetic field.

In which direction does the force act on a moving charge in a magnetic field?

It acts perpendicular to both the velocity of the charge and the magnetic field.

What is the formula for calculating magnetic force on a moving charge?

F = q(v × B), where F is the force, q is the charge, v is the velocity, and B is the magnetic field.

What happens to the path of a charge moving perpendicular to a uniform magnetic field?

The charge moves in a circular path.

What is the role of charge polarity on the direction of force in a magnetic field?

Positive charges follow the right-hand rule, while negative charges follow the left-hand rule.

What happens to a moving charge parallel to the magnetic field?

It experiences no magnetic force and continues in a straight line.

What is the effect of velocity direction on the force magnitude on a moving charge?

Maximum force occurs when velocity is perpendicular to the magnetic field.

How does the speed of the moving charge affect the force?

The magnitude of the force is directly proportional to the speed.

Can a magnetic field do work on a moving charge?

No, a magnetic force does no work on a moving charge.

What occurs to a positively charged particle when entering a magnetic field at an angle?

It follows a helical path.

What is the significance of the right-hand rule in magnetic force?

It helps determine magnetic force direction on a positive moving charge.

What is the effect on the path when a charge moves at a high velocity in a strong magnetic field?

The charge will move in a smaller circle due to increased centripetal force.

What happens to the kinetic energy of a charge moving in a magnetic field?

It remains constant because the magnetic force does no work.

What components of force are present in the Lorentz force?

It has both electric (qE) and magnetic (qvB) components.


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1. What is the force experienced by a moving charge in a magnetic field?

Electromagnetic force expressed as F = qE

Lorentz force given by F = q(v × B)

Centripetal force defined as F = q(v · B)

Gravitational force represented by F = mg

2. What are the factors that influence the magnitude of force on a moving charge?

Voltage, resistance, and capacitance

Charge magnitude, velocity, and magnetic field strength

Electric field, magnetic flux, and charge conductance

Charge distribution, magnetic permeability, and velocity gradient

3. In which direction does the force act on a moving charge in a magnetic field?

Parallel to the velocity

Perpendicular to both the velocity and the magnetic field

Along the magnetic field lines

In the opposite direction of the velocity

4. What is the formula for calculating magnetic force on a moving charge?

F = qE + vB

F = q(v × B)

F = q(v · B)

F = q + vB

5. What happens to the path of a charge moving perpendicular to a uniform magnetic field?

The charge moves in a circular path.

The charge moves in a straight line.

The charge moves in a spiral path.

The charge moves erratically without a defined path.

6. What is the role of charge polarity on the direction of force in a magnetic field?

Polarity increases force magnitude but doesn't change direction.

Positive charges follow the left-hand rule, negatives the right-hand rule.

Positive charges follow the right-hand rule, while negative charges follow the left-hand rule.

Polarity has no effect on force direction in a magnetic field.

7. What happens to a moving charge parallel to the magnetic field?

It experiences no magnetic force and continues in a straight line.

It experiences maximum magnetic force.

It moves in a circular path.

It accelerates parallel to the magnetic field.

8. What is the effect of velocity direction on the force magnitude on a moving charge?

Maximum force occurs when velocity is perpendicular to the magnetic field.

Maximum force occurs when velocity is parallel to the magnetic field.

Velocity direction has no effect; only speed matters.

Force magnitude is the same regardless of velocity direction.

9. How does the speed of the moving charge affect the force?

The speed does not affect the force magnitude.

The magnitude of the force is directly proportional to the speed.

The force magnitude decreases with increasing speed.

The force magnitude is inversely proportional to the speed.

10. Can a magnetic field do work on a moving charge?

Yes, by changing both speed and direction.

No, a magnetic force does no work on a moving charge.

Yes, but only under the influence of an electric field.

Yes, by accelerating the charge in the field direction.

11. What occurs to a positively charged particle when entering a magnetic field at an angle?

It follows a helical path.

It stops and remains motionless.

It continues in a straight line.

It rebounces back in the opposite direction.

12. What is the significance of the right-hand rule in magnetic force?

It identifies magnetic field strength only.

It helps determine magnetic force direction on a positive moving charge.

It dictates the velocity value needed for electrical conduction.

It measures the charge of particles in a magnetic field.

13. What is the effect on the path when a charge moves at a high velocity in a strong magnetic field?

The charge will move in a smaller circle due to increased centripetal force.

The charge path remains unaffected by speed or field strength.

The charge spirals outwards from the magnetic field.

Motion becomes linear due to overwhelming velocity.

14. What happens to the kinetic energy of a charge moving in a magnetic field?

It remains constant because the magnetic force does no work.

It increases due to work done by the magnetic force.

It decreases, losing energy to the field.

It fluctuates with direction changes in motion.

15. What components of force are present in the Lorentz force?

Magnetic component only (qvB)

Gravitational and inertial forces

It has both electric (qE) and magnetic (qvB) components.

Thermal and electrical conduction elements