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RAD Electromagnetism
Question | Answer |
---|---|
Which of the following can be magnetized? a) Cobalt b) Nickle c) Gold d) Glass | a, b |
Electromagnets can be made using which of the following? a) AC Current b) DC current c) Both AC and DC current d) Batteries only | c |
Electromagnets can be/ are? a) Permanent Magnets b) Temporary Magnets c) Turned on and off by controlling the current flow to the solenoid d) Never be turned off | b, c |
To determine the direction of the magnetic flux/ magnetic lines of force which of the following is used? a) Right Hand Rule b) Left hand Rule | a |
A wire coiled into a helix shape will act like a magnet when current is passed through it. This coil is called a a) Electromagnet b) Capicitor c) Alternator c) Solenoid | d |
If you insert a piece of soft iron into the center of a solenoid, magnetic flux will a) Increase b) Decrease c) Stay the same | a |
Magnetic attraction is related to distance a) Directly b) Indirectly c) Inversley to the square of the distance | c |
If you double the distance from the magnet, the force of attraction will be a) 1/2 b) Double c) 1/4 d) 4 Times | c |
In order for mutual induction to occur a) a second coil of wire must be placed near the first coil b) DC current must be used c) AC current must be used d) All of the above | a, c |
The magnitude of induced current depends on a) Speed at which the wire cuts the magnetic flux lines b) Strength of the magnetic field c) Angle of the wires cutting through the field d) Number of wire turns in the solenoid | a, b, c, d |
True/False- Flux lines are directed from the South pole to the North pole of an electromagnet? | False |
True/False- Flux lines repel one another when in the same direction? | True |
True/False- Magnetic domains are randomly oriented in magnetized objects? | False |
EMF stands for a) Electromagnetic force b) Electromotive force c) Electron Moving Force | b |
When a wire moves through a magnetic field, a current is produced. Which angle of the wire cutting through the field will produce the highest current? a) 0º b) 45º c) 60º d) 90º | d |
A soft iron core is generally used in an electro magnet due to its a) retentivity b) permeability c) attractability | b |
True/False-Generators and motors both rely on electromagnetic force | True |
True/False-Generators convert electrical energy to mechanical energy | False |
When will an electrostatic field appear around a magnet? a) at all times b) only when the magnet is moving c) only when the magnet is stationary | b |
A coil of wire that may be used as as a remote control magnet is called a) Rheostat b) Armature c) Solenoid d) Relay | d |