D.3 Motion in electromagnetic fields Flashcards
Electric Field Strength (E)
The force per unit charge experienced by a small positive test charge placed in the field
Equation for Electric Force (F)
F = qE, where q is the charge and E is the electric field strength.
Uniform Electric Field
A field in which the electric field strength is constant in magnitude and direction.
Direction of Electric Force on a Positive Charge
In the direction of the electric field lines.
Direction of Electric Force on a Negative Charge
Opposite to the direction of the electric field lines.
Magnetic Field Strength (B)
A vector quantity that represents the magnitude and direction of a magnetic field.
Lorentz Force
The force exerted on a charged particle moving through a magnetic field, perpendicular to both the velocity of the particle and the magnetic field
Right-Hand Rule for Magnetic Force
Thumb points in the direction of velocity, fingers in the direction of magnetic field, and palm points towards the force on a positive charge.
Circular Motion of Charged Particle
Occurs when a charged particle moves perpendicular to a uniform magnetic field, resulting in a centripetal force.
Radius of Circular Motion (r)
Determined by r = mv/(qB), where m is mass, v is velocity, q is charge, and B is magnetic field strength.
Equation for Magnetic Force (F)
F = qvB sin(θ), where q is charge, v is velocity, B is magnetic field strength, and θ is the angle between velocity and magnetic field.
Maximum Force on a Charged Particle
Occurs when θ = 90°, making sin(θ) = 1.
Zero Magnetic Force
Occurs when θ = 0° or 180°, as the charged particle moves parallel or antiparallel to the magnetic field.
Factor Affecting Magnetic Force
Velocity of the charged particle, magnitude of charge, magnetic field strength, and the angle of motion relative to the magnetic field.
What is the measurement unit for magnetic field strength?
Tesla (T)
Direction of Magnetic Field Around a Current-Carrying Conductor
Determined by the right-hand grip rule: thumb points in the direction of conventional current, and fingers curl in the direction of the magnetic field.
Calculating the Force on a Wire in a Magnetic Field
F = ILB sin(θ), where “I” represents the current through the wire, “L” is the length of the wire within the magnetic field, “B” indicates the magnetic field strength, and “θ” is the angle between the direction of the current and the magnetic field.
Behavior of Magnetic Force in Parallel Current-Carrying Wires
The magnetic force is attractive when currents flow in the same direction and repulsive when they flow in opposite directions.
Application of Magnetic Force on Current-Carrying Conductors
Used in devices like electric motors and measuring instruments.
Permeability of Free Space (μ₀)
A constant that describes the extent to which a magnetic field can penetrate space.
