Chapter 17: Magnetic Fields Flashcards
What is a magnetic field?
“A magnetic field is a region of space around a magnet or moving electric charge where other magnets or moving charges experience a force.”
What is the unit of magnetic field strength?
“The unit of magnetic field strength is the tesla (T).”
What is the relationship between electric current and magnetic fields?
“An electric current generates a magnetic field around the conductor
What is the right-hand rule?
“The right-hand rule states that if you point your thumb in the direction of current flow in a wire
What is the magnetic force on a moving charge?
“The magnetic force on a moving charge is given by F = qvB sin(θ)
What is the Lorentz force?
“The Lorentz force is the total force on a charged particle due to both electric and magnetic fields: F = q(E + v × B)
What is the magnetic field around a straight current-carrying wire?
“The magnetic field around a straight wire carrying current is concentric circles centered around the wire
What is Ampère’s law?
“Ampère’s law relates the magnetic field around a closed loop to the current passing through the loop: ∮B · dl = μ₀I_enc
What is the magnetic force on a current-carrying wire?
“The magnetic force on a current-carrying wire is given by F = BIL sin(θ)
What is the concept of a magnetic dipole?
“A magnetic dipole is a system with a north and south pole
What is the Earth’s magnetic field?
“The Earth’s magnetic field is a magnetic field that surrounds the Earth
What is the difference between a permanent magnet and an electromagnet?
“A permanent magnet has a constant magnetic field
What is the concept of magnetic flux?
“Magnetic flux is the measure of the amount of magnetic field passing through a given area
What is the unit of magnetic flux?
“The unit of magnetic flux is the weber (Wb)
What is Faraday’s law of induction?
“Faraday’s law of induction states that a changing magnetic flux induces an electromotive force (emf) in a closed loop: ε = -dΦ_B/dt.”
What is Lenz’s law?
“Lenz’s law states that the direction of the induced current is such that it opposes the change in magnetic flux that caused it.”
What is the concept of electromagnetic induction?
“Electromagnetic induction is the process by which a changing magnetic field induces an electric current in a conductor.”
What is the formula for the induced emf in a coil?
“The induced emf in a coil is given by ε = -N (dΦ_B/dt)
What is a solenoid?
“A solenoid is a coil of wire wound in a cylindrical shape that generates a magnetic field when current flows through it.”
What is the magnetic field inside a solenoid?
“The magnetic field inside a solenoid is uniform and given by B = μ₀nI
What is the concept of the magnetic force between two current-carrying wires?
“Two parallel current-carrying wires exert a force on each other. The force per unit length between two wires is given by F/L = μ₀I₁I₂ / (2πr)
