A ruby laser beam (l = 694.3 nm) is sent outwards from a 2.7-m diameter telescope to the moon, 384,000 km away. What is the radius of the big red spot on the moon?

a. 500 m
b. 250 m
c. 120 m
d. 1.0 km
e. 2.7 km


C

Physics & Space Science

You might also like to view...

You observe two stars that are identical to our Sun, but that are located at di?erent distances from Earth. Which star is the most luminous?

A) They are both the same luminosity. B) The one that appears brightest in our sky is more luminous. C) The one that appears faintest in our sky is more luminous. D) There is no way to tell from the information given.

Physics & Space Science

Two objects attract each other gravitationally. If the distance between their centers is cut in half, the gravitational force

A) is cut to one fourth. B) is cut in half. C) doubles. D) quadruples E) remains the same

Physics & Space Science

The two most plentiful elements in the universe are

A) hydrogen and oxygen. B) nitrogen and helium. C) carbon and oxygen. D) lithium and helium. E) hydrogen and helium.

Physics & Space Science

If ? = 4, which one of the following is a possible quantum number for n?

A) 0 B) 2 C) 3 D) 4 E) 8

Physics & Space Science