A ruby laser produces radiations of wavelength 662.6 nm in pulses whose duration are s. If the laser — Atomic Structure Chemistry Question

💡 Solution & Explanation

Total energy $E = 0.36$ J. $E = n \frac{hc}{\lambda} \implies 0.36 = n \times \frac{6.626 \times 10^{-34} \times 3 \times 10^8}{662.6 \times 10^{-9}} = n \times 3 \times 10^{-19}$. Solving for $n$ gives $n = \frac{0.36}{3 \times 10^{-19}} = 1.2 \times 10^{18}$ photons. Therefore, correct answer is C.