Magnetic Fields

Question 1

Lenz’s Law

Answer 1

Direction of induced emf/current is such as to oppose the change in flux producing it

Question 2

Faraday’s Law

Answer 2

Induced emf in a circuit is = to the rate of change of flux linkage through the circuit

Question 3

Magnetic Field Line

Answer 3

Direction a north pole would experience a force in the field around a magnet or a current carrying wire

Question 4

Tesla

Answer 4

Magnetic flux Density when 1A is flowing in 1m length of wire perpendicular to magnetic field lines and experiences 1N of force

Question 5

Flux

Answer 5

Number of flux lines
phi
Wb

Question 6

Flux Linkage

Answer 6

Number of flux lines that the coil is cutting through/ Number of flux lines x Turns on the coil
Nphi
Wb Turns

Question 7

Flux Density

Answer 7

Magnetic Field Strength/Flux lines per square metre
B
Tesla, Wbm^-2, Nm^-1A-1

Question 8

Rms I/V

Answer 8

Equal to the steady DC I/V that dissipates energy in the same rate at the same resistance