Q. Assuming the mass of Earth as $6.64 \times 10^{24}kg$ and the average mass of the atoms that make up earth as $40u$ (atomic mass unit), the number of atoms in the Earth are approximately
A) $10^{30}$
B) $10^{40}$
C) $10^{50}$
D) $10^{60}$
Explanation
$n \times 40\ amu = 6.64 \times 10^{24}$ $n \times 40 \times 1.6 \times 10^{- 27} = 6.64 \times 10^{24}$ $n = 10^{50}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.