C
Because in my opinion they do bending of a light wave as it passes at an angle from one medium to another.
Answer:
Explanation:
Let the volume of air be V. at atmospheric pressure, that is 10⁵ Pa
At 20 m below surface pressure will be
atmospheric pressure + hdg
10⁵ + 20 x 9.8 x 1000 = 2.96 x 10⁵Pa
At this pressure volume V becomes V/ 2.96
This volume will last 1/2.96 times time that is 60/2.96 = 20.27 minutes.
When the surface of the comb rubs on your hair, the comb is electrically charged. When the comb comes close to the paper, the charge on the comb causes charge separation on the paper bits. Since paper is neutral, positive and negative charges are equivalent. The charge on the comb charges the area of the bit of paper nearest the comb to the opposite. Thus, the bits of paper become attracted to the comb.
Answer:
I'm not sure if I know whatever the answer is