Q. If the work function of a photometal is $6.825\ eV.$ Its threshold wavelength will be $(c = 3 \times 10^{8}\ m/s)$
A) $1200\ \mathring{\mathrm{A}}$
B) $1800\ \mathring{\mathrm{A}}$
C) $2400\ \mathring{\mathrm{A}}$
D) $3600\ \mathring{\mathrm{A}}$
Explanation
(b) $\lambda_{0} = \frac{12375}{6.825} = 1813\ \mathring{\mathrm{A}} = 1800\mathring{\mathrm{A}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.