College Physics Problem 1.32

Calculate the approximate number of atoms in a bacterium. Assume that the average mass of an atom in the bacterium is ten times the mass of a hydrogen atom. (Hint: The mass of a hydrogen atom is on the order of 10^{-27} kg  and the mass of a bacterium is on the order of 10^{-15} kg .)


The number of atoms is

frac{m_{bact}}{10_{m_{H}}}=frac{10^{-15}}{10times10^{-27}}=10^{11} atoms