I_ _ _ _ r _ _ = heat energy

In order of decreasing light-transmitting capabilities of materials, which is the correct sequence? a. transparent -> translucent -> opaque b. opaque -> transparent -> translucent c. opaque -> translucent -> transparent d. translucent -> transparent -> opaque

Light from two different sources are incident upon the same side of a polarizing filter. light from one source is polarized with total intensity ip, while light from the other source is unpolarized with total intensity iu. as you rotate the polarizing filter through 360 degrees, the intensity of the transmitted light on the other side varies by a factor of 9. what is the relative intensity of the initial polarized source to the unpolarized source, or ip/iu?

The diagram shows a boulder rolling down a hill into a valley and then up the opposite hill. at which position does the boulder have the greatest kinetic energy? ab c d