Downloaded 249 times
More Related Content
Light Online
- 1.
- 2. Facts Light isenergy – electromagnetic energy (energy that is electric and magnetic) Travels in a straight path unless…it goes through a new material (medium) then it may bend or slow down Travels in waves Travels VERY fast! The speed of light: 186,000 mi/sec
- 3. How fast is186,000 miles/second?
- 4. Wavelengths We measurethe length of a light wave by measuring between two crests (high points) or troughs (low points). If the waves are close together, it has a short wave length. Far apart = long wave length
- 5. When light hitsa surface, it bounces or REFLECTS off of the surface. If light hits a smooth surface, it will bounce at a predictable angle. If light hits a rough surface, it bounces off at all kinds of angles.
- 6. Look at howthe surface affects these water reflections.
- 7. Con cave mirrors curve inward-like a “ cave ” Close up – image is enlarged, right-side up Further away – image is enlarged, but upside-down The further away you move, the smaller the image gets
- 8. Convex Mirrors curveoutward The image is always smaller and right-side up. Used for side view mirrors on cars, to prevent shoplifting, and in our stairwells here at school.
- 9.
- 10. Which is convex?Which is concave?
- 11. How light passesthrough objects Opaque completely blocks light from coming through Translucent Lets only part of the light through View is blurry Transparent Allows light to pass through with almost no disturbance Can be clear or colored Clear view
- 12. Refraction When lightrays bend as they are passing from one substance to another Happens when light rays pass through at an angle
- 13. Lenses – curvedtransparent materials that refract (bend) light to make images Convex lenses Curve out Light rays bend together after passing through “ e ” in conv e x = tog e ther
- 14. Convex lens –the rays angle together If the lens is close to your eye, the image you see will be right-side up and enlarged. If the lens is further away, the image will be upside down.
- 15. Concave Lenses Curvesinward (like a cave) Light rays pass through and move apart “ a ” in conc a ve = apart
- 16. Conc a veLens The image you see is always smaller and right-side up.
- 17. What would happenif you put both of them together? Hmm…..
- 18. Visible Light WavesWhite light is actually all the colors of light combined Each color of light has a different wave length Red has the longest; violet the shortest.
- 19.
- 20. When the lightray passes through a prism, the rays bend at different angles because their wave lengths are different
- 21. Since red’s wavelengthsare longer, they bend the least when passing through the prism Violet’s are shortest, so they bend the most.
- 22. Visible Light SpectrumA rainbow acts as a prism and a mirror. The sun shines through the drops of water (prism) and the backside of the raindrop is like a mirror, reflecting the bent colors back to us. BrainPop Rainbow
- 23. ROY G BIVHelps us remember the colors of the visible light spectrum. R = red O = orange Y = yellow G = green B = blue I = indigo V = violet Review with BrainPop!!!
- 24. How does colorwork? When light hits an object, it either reflects (bounces off) or is absorbed. An object’s color depends on which light waves are absorbed or reflected. If an object is yellow, it’s because all the colors except yellow are absorbed by the object. The yellow light is reflected back and what we see yellow!!
- 25. If none ofthe light colors are absorbed, then all of them reflect, and the object looks white.
- 26. If all areabsorbed, no light is reflected, and the object looks black.
- 27. Electromagnetic Spectrum Rememberthat visible light is electromagnetic energy that travels in waves Our eyes are only sensitive to the wavelengths of light from violet to red. Our eyes don’t pick up wavelengths shorter or longer than these
- 28.
- 29. BrainPop - ElectromagneticSpectrum