Question: Which of the following is smallest unit? [PMT/NEET-1996]
a. Millimetre
b. Angstrom
c. Fermi
d. Metre
Answer: c. Fermi
Solution:
$$1\ \text{m} > 1\ \text{mm}=10^{-3}\ \text{m} > 1\ \text{Ã…}=10^{-10}\ \text{m} > 1\ \text{fermi}=10^{-15}\ \text{m}$$
hence fermi is the smallest.
