Essential Questions
What is LIGHT?
Light
Luminous Objects Luminous objects emit (give off) their own light. Examples: The sun, a fire, glow-in-the-dark toys, watch faces, a filament (heated metal) in a lightbulb, and fireflies. Which are natural and which are artificial or man-made?
Non-Luminous Objects
Transparent
Translucent
Opaque
Look at these beams of light. How does the light seem to travel?
Light Travels in Straight Lines- Demonstrations
What’s so cool about lasers?
More About Lasers Brain Pop- Lasers
Light travels in transverse (S- shaped) waves.
Faster than a Speeding Bullet… Superman is said to fly “faster than a speeding bullet.” How does the speed of LIGHT compare? YouTube Video Clip Speed of Light Compared to Speed of a Bullet- YouTube Video Clip Speed of Light Compared to Speed of a Bullet- (2:12) YouTube Video Clip- How fast can light travel? (0:46) Light travels at 186,000 miles per second. Light from the sun reaches us in 8.3 minutes even though it’s 93 million miles away. A light year is the distance at which light can travel in a year’s time.
Light Absorption Why do we wear Light Colors in the Summer and Dark Colors in the Winter? What does this have to do with Light? Dark colors absorb more heat than light colors do. Demonstration
Light Reflection
What happens if the water isn’t still or if the object isn’t smooth or shiny? Almost every surface reflects some light otherwise we would not be able to see anything. Most surfaces are uneven or rough and when light rays strike these rough surfaces they bounce off in all directions. There is no clear image reflected.
How Do Mirrors Work? Real World Science- Light- Reflection Real World Science- Light- Reflection 1:16- Discovery Education Video
How Do Objects Bend Light? Refraction- When light moves from one medium to another, such as from air to water, it changes speed and direction. Disappearing Penny TrickDisappearing Penny Trick- You Tube Video (2:48) Students Demo these. Other Refraction Tricks- You Tube Video (2:07)Other Refraction Tricks- You Tube Video Real World Science- Light- Refraction, The Bending of Light RaysLight Rays (1:47) Discovery Education Video
Definitions- Things Light Can Do
Video Quiz
Why are red things red?
Video Clips on Color
What is a PRISM and what does it do to LIGHT? A prism is a piece of glass or plastic that can be used to show that white light is really made up of many colors. As the light moves through the prism, refraction causes the light to change speed and direction. Each wavelength of the light bends a little differently, so you see all the colors of a rainbow. How a Prism Works to Make Rainbow ColorsHow a Prism Works to Make Rainbow Colors (2:44) YouTube Video
Definitions-Types of Lenses
Convex Lenses Convex lenses take in light and bend it to a single focus point. This makes objects seem closer and you are able to see in greater detail. That image is upside down. Up close, a magnifying glass image isn’t upside down, but look at something far away and it is. Your eyes send an upside down image to your retina, but your brain turns it right side up. Mirrors help flip the images from binoculars and telescopes.
Concave Lenses Concave lenses spread light out over a larger distance. You can see a wider view, but objects seen through them appear to be smaller and more far away than they actually are. This is why your car side mirrors often have a warning printed on them, “Objects are closer than they appear.”
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