Revise later
SpaceTo flip
If confident
All Flashcards
Define magnetic field.
A region around a magnet or moving charge within which a magnetic force is exerted.
Define magnetic force.
The force exerted on a moving charge or current-carrying wire in a magnetic field.
Define Hall effect.
The creation of a potential difference (Hall voltage) across a conductor, transverse to an electric current in the conductor and a magnetic field perpendicular to the current.
Define velocity vector.
A vector quantity that represents the rate of change of an object's position with respect to time, including both speed and direction.
Define the term 'position vector'.
A vector pointing from a reference point to the current location of an object.
Define electric force.
The force exerted on a charged particle by an electric field.
What are the key differences between electric and magnetic forces?
Electric Force: Acts on both stationary and moving charges, acts along the field line. | Magnetic Force: Acts only on moving charges, acts perpendicular to both the velocity and magnetic field.
Compare the motion of a charged particle in an electric field versus a magnetic field.
Electric Field: Particle accelerates in the direction of (or opposite to) the field, resulting in a change in speed. | Magnetic Field: Particle moves in a circle (or helix) with constant speed, changing direction but not speed.
Compare the effect of force when the angle between velocity and magnetic field is 0 degrees and 90 degrees.
0 degrees: Force is zero, no effect. | 90 degrees: Force is maximum, particle experiences maximum deflection.
Compare the factors affecting the strength of magnetic and electric forces.
Magnetic Force: Depends on charge, velocity, magnetic field strength, and the angle between velocity and field. | Electric Force: Depends on charge and electric field strength.
Compare the effect of electric and magnetic fields on the kinetic energy of a charged particle.
Electric Field: Can change the kinetic energy of the particle by doing work on it. | Magnetic Field: Does not change the kinetic energy of the particle; it only changes the direction of motion.
How do you determine the direction of the magnetic field created by a moving positive charge?
Use the right-hand rule: Thumb in the direction of velocity, fingers in the direction of the position vector from the charge. Palm points in the direction of the magnetic field.
How do you determine the direction of the magnetic force on a moving positive charge in a magnetic field?
Use the right-hand rule: Thumb points in the direction of velocity, fingers point in the direction of the magnetic field. Palm points in the direction of the force.
How do you determine the direction of the magnetic force on a moving negative charge in a magnetic field?
Use the right-hand rule: Thumb points in the direction of velocity, fingers point in the direction of the magnetic field. Palm points in the direction of the force. Reverse the direction of the palm to find the force on a negative charge.
Steps to calculate magnetic force.
1. Identify charge (q), velocity (v), magnetic field (B), and angle ($\theta$). 2. Use the formula $F_{B} = q v B \sin \theta$ to find the magnitude. 3. Use the right-hand rule to find the direction.
Describe the steps to determine the radius of the circular path a charged particle follows in a uniform magnetic field.
1. Equate the magnetic force ($qvB$) to the centripetal force ($mv^2/r$). 2. Solve for the radius, $r = mv/qB$.