rays

A ray is a line that has one endpoint and goes on forever in one direction. It can be used to represent light, heat, or sound.

For example, when you shine a flashlight, the light travels in rays from the flashlight to the objects that it hits. The rays of light are invisible, but you can see the light that they hit.

Another example of rays is the heat that comes from the sun. The heat travels in rays from the sun to the Earth. You can't see the rays of heat, but you can feel the heat that they hit.

Rays are important because they help us to understand how light, heat, and sound travel.

The sun's rays shine down on the earth.".