Motors And Generators Flashcards
Motor effect
A current carrying wire in a magnetic field experiences a force.
Parallel wires formula
F = k i1i2L / d
What is magnetic flux density?
The number of field lines that cut a coil or conducting disk.
What are eddy currents?
Large circular currents due to changing magnetic flux density.
What is Faraday’s law?
A change in magnetic field induces a current.
A change in magnetic flux induces a current.
What is Lenz’s law?
If an induced current flows, it’s direction always opposes the change in flux that produced it.
Formula for forces acting on current carrying conductors?
F = nBILsin
What are the torque formulas ?
T = Fd
T = nBIAcos
The motor effect in a galvanometer
Is used to measure the magnitude of an electric current. Current is passed through a coil suspended in the field of a permanent u shape magnet. The motor effect produces a torque on the coil in proportion to the magnitude of current.
