Page 138 - Knowledge Organiser Yr8 24-25

Knowledge Base: Science 8.7 Electromagnetic Waves Year 8
1. Light
1.1
1.4
1.6
How does light travel?
What is the speed of light?
What is a light year?
In waves that are straight lines.
300,000,000 m/s.
The distance light travels in one year.
2. Reflection
2.1 What is reflection?
When light bounces off an object and into your eyes.
1.2
What happens if light hits a solid object?
It will cast a shadow.
1.3
How can light travel through a vacuum?
Because light is a transverse wave and waves do not need particles (a medium) to travel through.
2.2
What is the ray of light called that leaves the light box and hits a mirror?
The incident ray.
2.3
What is the ray of light called that reflects off the mirror and into your eyes?
The reflected ray.
2.4 What is the normal?
An imaginary line drawn at 90o to the mirror.
1.5
What travels faster: light or sound?
Light.
2.5
Draw and label a diagram to show light reflecting off a mirror.
2.6
What is the law of reflection?
The angle of incidence is equal to the angle of reflection.
1.7
What does it mean if an object is luminous?
It emits its own light.
1.8
Give an example of a source of light.
The Sun or a light bulb.
1.9
What does it mean if an object is non-luminous?
It will not produce its own light, instead it will reflect light.
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