Magnetism

Question 1

What are the properties of magnetic field lines?

Answer 1

1. They always go from N to S

2.the arrows show the direction of a free north pole

3. Equally spaced and parallel lines indicate INF uniform magnetic field

Question 2

Field going in the paper and out of the paper . How is it represented ?

Answer 2

Going in the paper

(×) (×) (×)
(×) (×) (×)
(×) (×) (×)

Going out of the paper

(•) (•) (•)
(•) (•) (•)
(•) (•) (•)

Question 3

Flemming’s left hand rule : what does each finger represent?

Answer 3

Thumb = motion= force

First finger = field

Second finger = current

Question 4

What does a magnetic field around a current carrying wire consist of?

Answer 4

Concentric circles that are perpendicular to the plane of motion of current

Question 5

If the current of the current carrying wire is going into the screen, what is the direction of the magnetic field?

Answer 5

Clockwise

Question 6

If the current of the current carrying wire is going out of the screen, what is the direction of the magnetic field?

Answer 6

Anticlockwise

Question 7

What is the definition of magnetic flux density B?

Answer 7

It is the force per unit current per unit length on a currant carrying conductor that is placed perpendicular to the B field.

B=f/il

Question 8

What is the definition of a Tesla? which is the unit of magnetic flux density B

Answer 8

It is the magnetic flux density that causes a force of 1N on a wire with the length of 1m and a current of 1A is going through the wire when the wire is at 90 degrees to the B field