Let’s see how you did! If you didn’t get a few of these, don’t let it stress you out – it just means you need to play with more experiments in this area. We’re all works in progress, and we have our entire lifetime to puzzle together the mysteries of the universe!
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1. Light can change speed the same way sound vibrations change speed. (Think of how your voice changes when you inhale helium and then try to talk.) The “speed limit” of light is 186,282 miles per second – that’s fast enough to circle the Earth seven times every second, but that’s also inside a vacuum. You can get light going slower by aiming it through different gases. In our own atmosphere, light travels slower than it does in space.
2. No. Human eyes can only detect a small portion of all light (in the visible range).
3. Red light has a LONGER wavelength and LESS energy than blue light.
4. Campfire, the sun, and a neon OPEN sign.
5. No. Radio waves are LIGHT waves that are very low energy and have a loooooong wavelength.
6. By aiming light beams at your food which are specially tuned to excite the water molecule. Since all foods have water, this works to heat up your food. Excited molecules are ones that jiggle and zip around fast, which is also called heat
7. Both use IR (infrared) light. The snake is a detector and the TV remote is an emitter.
8. Longwave UV are black lights you can get around Halloween that make things glow and fluoresce, and these types of lights are not damaging to living tissue even though they have more energy than visible light. Short wave UV (which have shorter wavelengths and more energy), however, are damaging and can burn your skin.
9. Both, and you really can’t separate the two.
10. When you aim a blue light on a metal plate, electrons shoot off the surface. Red light doesn’t cause electrons to eject, however, no matter how bright you make the red light. It’s the wavelength, not the intensity that matters with the photoelectric effect.
11. Mix together green and red light to get yellow light. Yellow paint is a fundamental color that can’t be made from any others – you have to start with yellow.
12. A prism un-mixes the light beams into its separate colors.
13. The sunglasses need to be 90 degrees from each other.
14. The pencil appears bent (or broken) because the water and the glass change the speed of light. Depending on where your line of sight is, you can make the pencil appear broken or whole.
15. Besides hiding it in a closet, you can also place a Pyrex glass container inside a glass container filled with mineral oil, vegetable oil, or light Karo syrup. The index of refraction is the same for both, so our eyes are unable to see the difference between the two.
16. A microscope uses lenses that bend the light to make things appear larger. Using two convex lens magnifiers, you can find the tiny owl in the upper corner of the dollar bill that’s normally hidden to the naked eye.
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