Light, Shadows & Materials Lab

Shine a light on different materials and watch what happens. Some materials let light pass through, some block it completely, and some do a little of both. Record how each material changes the shadow and find the pattern.

Guided Experiment: Materials and Shadows Investigation

Look around the room. Do you think every thick material blocks light the same way? Predict whether all thick materials cast dark shadows, or if some still let a little light through.

Write your hypothesis in the Lab Report panel, then click Next.

Pick a Material

Watch the Shadow

Ground

Clear Glass

Light passes straight through — you can see clearly.
Light Propertytransparent
Lets Light Through?Fully
Shadow Strength
0 / 3
Shadow. No shadow forms.

Controls

0 / 500
0 / 500
0 / 500

Reference Guide

How Light Travels

Light travels in straight lines from a source like the sun, a lamp, or a flashlight. When light hits an object, something has to happen. It can pass through, bounce off, or get stopped.

Sun. Makes sharp outdoor shadows.
Lamp. Makes softer indoor shadows.
Flashlight. Makes a focused beam.

Whether a shadow forms, and how dark it is, depends on the material the light hits.

Three Kinds of Materials

Scientists group materials by how much light passes through them. Every material in the lab is one of these three kinds.

Transparent. Lets all light through. Clear glass, water.
Translucent. Lets some light through. Tissue paper, frosted glass.
Opaque. Blocks all light. Wood, rock, cardboard.

The word transparent means you can see straight through. Opaque means you cannot see through at all.

What Makes a Shadow

A shadow forms when an object blocks light from reaching a surface. The darker the shadow, the less light is getting through.

No shadow. All light passes through.
Faint shadow. Most light passes through.
Partial shadow. Some light is blocked.
Dark shadow. All light is blocked.

The shape of the shadow matches the shape of the object. Your own body makes a body-shaped shadow on a sunny day.

Try This at Home

Grab a flashlight and a few items from around the house. Point the flashlight at a wall and hold each item between the light and the wall.

Drinking glass. Transparent. Almost no shadow.
Wax paper. Translucent. Faint, blurry shadow.
Book. Opaque. Sharp, dark shadow.

Sort your items into transparent, translucent, and opaque. Add any new ones you find to the Data Table as you go.