College Physics Problem 1.33


Approximately how many atoms thick is a cell membrane, assuming all atoms there average about twice the size of a hydrogen atom?


Solution:

The cell membrane is 10-8 m while the hydrogen atom is 10-10  m. The number of atoms in the cell membrane is

\displaystyle \text{no. of atoms}=\frac{\text{d}_{\text{m}}}{2\text{d}_{\text{H}}}=\frac{10^{-8}}{2\left(10^{-10}\right)}=50\:\text{atoms}          ☚