Light travels in

• A curved line

• Pulses

• A straight line

• Currents

Light is the ------- thing in the universe

Transparent materials that allow light to pass through --------- light

Light is scattered by an object with a rough surface

The angle of incidence is equal to the angle of reflection

When light hits something transparent, its -------and ------ change

• Colour

• Speed

• Frequency

• Direction

What is it called when light hits a transparent surface and its speed and direction change?

What is the focal point?

What is the focal length?

Rod cells in our retinas detect