How Light Travels

Light travels in straight lines at 300,000 km per second. Shadows, umbra, penumbra. Class 7 Science with quiz.

Class 7 ScienceClass 7 / Grade 7Ages 9–12
Lesson
💡 How Light Travels
Light travels in straight lines!☀️ray of lightopaque objectshadowLight travels at 300,000 km/s — fastest in the universe!

Light is a form of energy that enables us to see. Light travels in straight lines — this is called rectilinear propagation. The speed of light is approximately three hundred thousand kilometres per second, making it the fastest thing in the universe. We can see objects because light from a source hits them and bounces into our eyes. Objects that produce their own light are called luminous objects — the sun, stars, fire, and electric bulbs. Objects that only reflect light from luminous sources are non-luminous — the moon, planets, and most things around us.

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