Question

The energy of a photon is $3\times {10}^{-12}ergs$. What is its wavelength in nm ? ($h$ = $6.62\times {10}^{-27}erg.Sec$; $c$ = $3\times {10}^{10}cm.s^{-1})$

• A. 662 nm
• B. 1324 nm
• C. 66.2 nm
• D. 6.62 nm

Answer 1

The correct option is A

662 nm

$\lambda =\frac{hc}{E}=\frac{6.62\times {10}^{-27}\times 3{10}^{10}}{3\times {10}^{10}}=662nm$