Author Question: The mass of the Sun is 2.0 1030 kg, and the mass of a hydrogen atom is 1.67 10-27 kg. If we assume ... (Read 115 times)

Ebrown · **on:** Jul 28, 2018

The mass of the Sun is 2.0 1030 kg, and the mass of a hydrogen atom is 1.67 10-27 kg. If we assume that the Sun is mostly composed of hydrogen, how many atoms are there in the Sun?
a. 1.2 1056 atoms
c. 1.2 1057 atoms
b. 3.4 1056 atoms
d. 2.4 1057 atoms

Question 2

When NASA was communicating with astronauts on the moon, the time from sending on the Earth to receiving on the moon was 1.28 s. Find the distance from Earth to the moon. (The speed of radio waves is 3.00 108 m/s.)
a. 240,000 km
c. 480,000 km
b. 384,000 km
d. 768,000 km