What does Morse code use to represent letters of the alphabet?

Fill in the gaps:
This code is used by signalling lamps as a series of short and long ....... .. ......

Finish the sentence:
When a signal is sent by light, electricity, microwaves or radio, it is almost ..............

Each method of transmission has advantages and disadvantages. Name what these could be.

What is white light made up of?

Name the three features about laser light.

Laser light is used to do what?

How does this work?

What normally happens when light travels from one material to another.

If it is passing from a more dense material into a less dense material, is the angle of refraction larger or smaller than the angle of incidence?

Draw a labelled diagram to show what happens when light exits a glass block.

What is the angle of incidence called when the angle of refraction is 90°?

Draw a labelled diagram to show what happens when the angle of incidence is at the critical angle.

If the angle of incidence is bigger than the critical angle, the light is reflected. What is this called?

Draw a labelled diagram to show total internal reflection.

What are telephone communications and computer data are transmitted long distances along?

Fill the gaps:
Some ...... are coated to improve ...........

What is an optical fibre?

What is an endoscope and what does it allow doctors to do?

How does an endoscope work?