Chapter 8 Light and Sound O’Neal 4th Grade Team

Chapter 8 Vocabulary Visible Spectrum: light energy that can be seen and can be broken into the colors of light in the rainbow. Ray: a narrow beam of light that travels in a straight line from a light source. Transparent: allows light to pass through so that whatever is behind can be seen. Opaque: does not allow light to pass through. Absorb: to take in. Reflect: to bounce back. Transmit: to pass through. Convex lens: a lens that is thicker in the middle than at the edges. Concave lens: a lens that is thinner in the middle than at the edges. Wavelength: the distance from a point on a wave to the same point on the next wave. Vibrate: to move quickly back and forth.

What is light Name the colors you see in a rainbow. When do you usually see a rainbow? Sun bends and reflects off the water drops in the air resulting in a rainbow.

What is light? Sources of Light

How does light travel? Light is a kind of energy. Light travels in a straight line until it strikes an object. When light bounces back from an object, it is called reflected light.

How does light travel? Light can be reflected in different amounts. Smooth objects, like mirrors, reflect light very well.

Rough objects or ones that are black or dark do not reflect light as well.

If you were in a dark cave and pointed the beam of your flashlight at a wall of dark, rough rocks, you would still find it difficult to see.

If the cave wall were made of light, smooth rocks, they would not absorb as much light and you would find it easier to see.

When light passes through water or glass, it slow down and light bends.

When light bends, we say it is refracted.

Can you explain this picture?

How are light and sound similar and different?

Chapter Review