Electrodynamics Flashcards
State Faraday’s Law:
Faraday’s Law:
The emf induced is directly proportional to the rate of change of magnetic flux.
Define alternating current:
Current which reverses direction periodically.
What is a commutator:
A commutator is a device which ensures that the direction of the current in a coil is reversed every half revolution.
Define direct current:
Current flowing in one direction only.
What is electromagnetic induction?
Electromagnetic Induction is the process of using magnetic fields to produce voltage, and in a closed circuit, a current.
What is meant by the term “induced emf?”
Induced emf:
The total amount of electrical energy supplied per unit positive charge.
Define magnetic fields:
Magnetic fields:
Magnetic fields are produced by magnets or by moving electrical charges. Magnetic field lines are drawn to represent the direction of a magnetic field at a point.
Define magnetic flux density:
Magnetic flux density:
A representation of the magnitude and direction of the magnetic field
Define magnetic flux:
Magnetic flux:
For a loop of area (A) in the presence of a uniform magnetic flux density (B), the magnetic flux (Φ) passing through the loop is defined as Φ = BAcosθ, where θ is the angle between the magnetic flux density (B) and the normal to the loop of the area (A).
Define magnetic flux linkage:
Magnetic flux linkage:
Magnetic flux linkage is the product of the number of turns on a coil and the flux through a coil.
State Lenz’s Law:
Lenz’s Law:
The induced current flows in a direction so as to set up a magnetic field to oppose the change in magnetic flux.
What is a diode?
A diode is a component that only allows current to flow in one direction.
What is a generator?
A device that converts mechanical energy into electrical energy.
What is a motor?
A device that converts electrical energy into mechanical energy.
