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WorksheetsCh1_part1_EPO460
Total questions: 20
Worksheet time: 3mins
Which material shows strong attraction to magnetic fields and retains its properties after the external field is removed?
Diamagnetic
Paramagnetic
Ferromagnetic
Non-magnetic
Magnets always have:
One pole only
Two poles
Four poles
No poles
Which of the following is a permanent magnet?
Transformer core
Fridge door magnet
Paper clip
Electromagnet in a motor
What happens to a temporary magnet (e.g. a nail near a magnet) once the external magnet is removed?
It stays magnetised forever
It loses magnetism after a short time
It turns into a permanent magnet
It becomes diamagnetic
An electromagnet becomes stronger when:
Current is reduced
Coil is replaced with a straight wire
Core is ferromagnetic
Air is used as core
The symbol for magnetic flux is:
H
B
Φ
M
The unit of magnetic flux density (B) is:
Weber (Wb)
Tesla (T)
Ampere-turn (At)
Henry (H)
Which rule is used to find the direction of magnetic field around a current-carrying conductor?
Fleming’s left hand rule
Fleming’s right hand rule
Right-hand grip rule
Lenz’s law
Faraday’s first law states:
A coil stores energy in magnetic field
A conductor cutting magnetic flux induces EMF
Current flows in a closed loop only
Flux density is proportional to magnetising force
Does the fringing effect increase if the air gap length increases?
True
False
Fleming’s left-hand rule is used for:
Generators
Motors
Transformers
Inductors
Which law explains that induced EMF opposes the change that caused it?
Faraday’s law
Lenz’s law
Fleming’s rule
Ampere’s law
Does leakage flux follow the intended path in a magnetic circuit?
True
False
The relationship between H and i can be described by:
Ohm’s law
Faraday’s law
Ampere’s law
Fleming’s law
The permeability of free space (μ₀) is:
4π × 10⁻⁷ H/m
3 × 10⁸ H/m
4.1π × 10⁻⁶ H/m
9.81 m/s²
Can electromagnetism occur without an electric current?
True
False
Which term refers to the property of a material to conduct magnetic flux?
Reluctance
Permeability
Resistance
Inductance
In the B-H curve, what happens at high values of H?
B increases linearly
B decreases to zero
B shows saturation
B becomes infinite
Do all materials respond to magnetic fields?
True
False
Is useful flux the one that passes through the core and is utilised?
True
False
