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Flashcards in P7 Deck (15):
1

What are the poles of a magnet?

Places where the magnetic forces are strongest. When two magnets are brought close together they exert a force on each other. Two poles repel each other . Two unlike poles attract each other. Attraction and repulsion between two magnetic poles are examples of non contact forces.

2

What do compasses show?

Compass points to the direction that the magnetic field is in

3

What is a permanent magnet?

Produces its own magnetic field

4

What is an induced magnet?

Material that becomes a magnet when it is palced in a magnetic field. Induced magnets always cause a force of attraction. When removed from a magnetic field an induced magnet loses all of its magnetism quickly

5

What is a magnetic field ?

A region around a magnet where a force acts on another magnet or on a magnetic material (iron,steel,cobalt and nickel) is called the magnetic field.

6

What is always the force between a magnet and a magnetic material?

A force of attraction

7

What does the strength of the magnetic field depend on?

Distance from the magnet. The field is strongest at the poles of the magnet

8

What effects the direction of a magnetic field?

Given by ghe direction of the force that would act on another north pole placed at the point. The direction of a magnetic field line is from the north pole of a magnet to the south pole of a magnet

9

How do compasses show the earths magnetic fields?

Contain a small bar magnet. The earth has a magnetic field. The compass needle points in the direction of the earths magnetic field

10

What is createdwhen a current flows through a conducting wire ?

A magnetic field is produced around the wire. The strength of the magnetic field depends on the current through the wire and the distance around the wire.

11

What is a solenoid?

A coil of a wire. It increases the strength of the magnetic field created by a current through a wire. The magnetic field inside the solenoid is strong and uniform

12

What is the shape of the magnetic field around a solenoid?

Similar to the magnetic field around a bar magnet

13

How to increase strength of magnetic field of a solenoid?

Add an iron core .

14

What is an electromagnet?

A solenoid with an iron core

15

What is the motor effect?

When a current carrying wire is put between magnetic poles , the magnetic field around the wire interacts with the magnetic field it has been placed in . This causes the magnet and the conductor to exert a force on each other. This is called the motor effect and can cause the wire to move.