7.4 Electric Motors

Question 1

Flemings left hand rule

Answer 1

First finger - direction of magnetic Field
Second finger - direction of current
Thumb - direction of the force ( motion)

Question 2

What happens if a coil is on a spindle ?

Answer 2

The forces act one up and one down it rotates

Question 3

On a basic motor where do the force act on ?

Answer 3

Two side arms of a coil

Question 4

What does the split ring commuter do ?

Answer 4

Swapping the current every half turn to keep the motor rotating in the same direction

Question 5

How can the direction of the motor be reversed ?

Answer 5

Reversing the current (swapping the polarity of dc)

Swapping magnetic poles (reversing the field)

Question 6

How can a speed of a motor be increased?

Answer 6

By increasing the current , adding more turns to the coil or increasing magnetic flux Density

Question 7

If the coal is rotating what is happening?

Answer 7

Coil is on spindele and forces act one up and one down