Transformers

Question 1

What happens if a magnet is moved into a coil of wire

Answer 1

A potential difference is induced across the ends of the coil

Question 2

What does an alternating current in the primary coil produce

Answer 2

A changing magnetic field in the iron core hence the secondary coil

Question 3

What happens in a step up transformer

Answer 3

The potential difference across the secondary coil is greater than the potential difference across the primary coil

Question 4

What happens in a step down transformer

Answer 4

The potential difference across the secondary coil is less than the potential difference across the primary cool

Question 5

When do switch mode transformers operate

Answer 5

At a high frequency often between 50 kHz and 200kHz

Question 6

When happens when switch mode transformers are switched on

Answer 6

They use very little power and no load is applied

Question 7

What happens if an electrical conductor cuts through a magnetic field

Answer 7

A potential difference is induced across the ends of the conductor