1. How Does Light Travel?
Lesson 3

2. How does light travel?

3. How does light travel?

4. Speed of Light: About 300,000 km/sec About 186,000 miles/sec
Fastest known thing in the universe.
Speed of light is the “c” in E=mc2
A light year is the distance light can travel in one year. (A light year is about 5,500,000,000,000 miles.)

5. Mirror on the Moon

6. Light travels in straight lines called rays.
Big Ideas:
Light is invisible as it travels and we can only see light if it bounces off something (like fog or the wall).
Light travels in straight lines called rays.
Light travels very quickly (~300,000 km/sec).