Question

A typical atomic nucleus is about 5 × 10−15 m in radius. Use the uncertainty principle to place a lower limit on the energy an electron must have if it is to be part of a nucleus. 

Answer 1

Answer

For uncertainty

$P=\frac{\hbar}{r}\\=2.11*10^{-20}kg-m/s$

Now energy

$E=\sqrt{p^2c^2+m^2c^4}$

Putting all values

E=$3.3*10^{-12}J$