Question

The wavelength of a photon needed to remove a proton from a nucleus which is bound to the nucleus with 1 MeV energy is nearly

• A. $1.2\times {10}^{1}nm$
• B. $1.2\times {10}^{-6}nm$
• C. $1.2nm$
• D. $1.2\times {10}^{-3}nm$

Answer 1

The correct option is D $1.2\times {10}^{-3}nm$

Given, energy of the proton
$E=1MeV={10}^{6}eV$
$E=\frac{hc}{\lambda }$
$E=\frac{1240eVnm}{\lambda }$
$\lambda =\frac{1240}{{10}^6}nm$
$=1.24\times {10}^{-3}nm$


Final Answer: $\left(b\right)$