6

Lesson 6 of 84 ยท Human Impacts on Earth

Experiment

How Light Travels

What You'll Learn

Light travels in straight lines and can be reflected, refracted, or absorbed. Mirrors reflect light, lenses refract (bend) light, and dark surfaces absorb light.

Key Words

  • observation
  • experiment
  • conclusion

Materials Needed

  • pennies
  • plastic wrap
  • cardboard
  • tape
  • scissors
  • straws

Safety First

  • Use materials only as directed in the experiment.
  • Keep small objects away from young children.
  • Work in a well-ventilated area when using vinegar or other strong-smelling substances.

Steps

Step 1 โ€” Read

Read about Human Impacts on Earth and write down three key facts.

Step 2 โ€” Do

Design an experiment to test a hypothesis. Identify your independent variable, dependent variable, and controls. Run the experiment and present results.

Step 3 โ€” Observe

Compare the before and after states.

Step 4 โ€” Record

Write your conclusion: did the results match your hypothesis? What would you change next time?

Check Your Understanding

Question 1

1 of 3

What is sound?

How Light Travels โ€” Human Impacts on Earth | 7th Grade Science | LittleActivity | LittleActivity