Author Question: A beam of light in air is incident on the surface of a rectangular block of clear plastic (n = ... (Read 70 times)

Marty · **on:** Jul 28, 2018

A beam of light in air is incident on the surface of a rectangular block of clear plastic (n = 1.40). If the speed of the beam before it enters the plastic is 3.00 108 m/s, what is its speed inside the block?
a. 2.14 108 m/s
c. 1.94 108 m/s
b. 2.01 108 m/s
d. 3.00 108 m/s

Question 2

I take 2.0 kg of ice and dump it into 1.0 kg of water and, when equilibrium is reached, I have 3.0 kg of ice at 0C. The water was originally at 0C. The specific heat of water = 1.00 kcal/kgC, the specific heat of ice = 0.50 kcal/kgC, and the latent heat of fusion of water is 80 kcal/kg. The original temperature of the ice was:
a. one or two degrees below 0C.
c. -120C.
b. -80C.
d. The whole experiment is impossible.