A material has an index of refraction of 1.92 for light from a ...

[sarasara]

A material has an index of refraction of 1.92 for light from a 560 nm source. What is the speed of light for this wavelength within the material? (c = 3.00  108 m/s)
 a. 2.19  108 m/s
  c. 1.56  108 m/s
  b. 4.68  108 m/s
  d. 1.92  108 m/s

Question 2

Metal lids on glass jars can often be loosened by running them under hot water. Why is this?
 a. The hot water is a lubricant.
  b. The metal and glass expand due to the heating, and the glass being of smaller radius expands less than the metal.
  c. The metal has a higher coefficient of thermal expansion than glass so the metal expands more than the glass, thus loosening the connection.
  d. This is just folklore.

[jaygar71]

Answer to Question 1

C

Answer to Question 2

C

[sarasara]

TYSM

[gcook]

Excellent