What is a solenoid?
A long thin spiral of wire used to produce a magnetic field
An imaginary line used to measure the strength of a magnetic field
A type of force exerted from the north pole of a magnet
What happens to the magnetic field around an electromagnet when the current is reversed?
It reverses for a short time and changes back
Nothing
It reverses
What do field line patterns show?
The direction and shape of a magnetic field
The shape of a magnetic field only
The direction of a magnetic field only
Which of these induces a bigger voltage in electromagnetic induction?
Reducing the number of coils
Increasing the area of the coil
Using a weaker magnet
How would you define the motor effect?
A current carrying wire exerting a force on an electromagnet
A current carrying wire exerting a force on a temporary magnet
A current carrying wire exerting a force on a permanent magnet
What does your thumb point to in the left hand rule?
The direction of motion
The direction of the magnetic field
The direction of the current
If you have the following values in a transformer, what is V2?
V1 = 240
N1 = 100
N2 = 1,500
3,600
625
16
In a generator, one side of a coil moves up during one half turn and then down during the next half turn. This means that as a coil is rotated in a magnetic field, the induced current reverses direction every half turn. What type of current is this?
Alternating current
Direct current
Static current
What do transformers change?
An alternating voltage
A direct voltage
Both alternating and direct voltages
What is induced in the core of a transformer?
Electricity
Iron
A magnetic field