Unit 10: turn out the LIGHTS

Today we learned more about how light works. We cannot actually see light because light is invisible. We can see light's reflection and the light emitter. The light emitter is a thing that emits light so that we can see it. The path that light takes is a straight line. Lights from the ceiling emit light downwards in a straight line and reflects off of the floor or tables or anything in it's way so we can see things. The primary colors of light are red, green and blue. Opposite color of red is cyan, green is magenta, blue is yellow. We learned that the sky is blue because of scattering of light in the upper atmosphere, not because it's reflecting off of the ocean. The ocean is blue because it absorbs red wave lengths. The lower the frequency, the higher the wave length. Frequencies will be what defines the waves. ROYGBIV are the colors. Red has the lower frequency and violet has a higher frequency. Ultraviolet waves are above violet, which have a ultra high frequency.

X-rays are high energy waves that can cause mutations in cells, skin burns and cancer. X-rays are opaque to bones, but transparent to skin and muscle. X-rays can see the bones, but ignore and make the skin and muscle invisible.

 

 

 

 

 

 

 

 

 

This picture shows how the light travels in a straight line all the time. These lasers are the light emitters and the light travels in a line. We can only see the ray of light because there is stuff in the air. Otherwise, we will not be able to see the light because light is actually invisible.

 

SHADOWS!! When there is one light source, there will be one shadow. When there are two light sources, there will be two shadows and so on. One this white board, the green light will make the board green and the red light will make the board red. When the red and green mix together they make yellow. The shadow that's blocking the red light will be green and vice versa with the green light. Where Mr. Blake is blocking both lights, the shadow will be black. (Mr. Blake is dancing :) )

This is just a picture of the light ray coming straight from the light emitter into the camera. :D