Home MCQs NEET Chemistry Question #7347
Back to Questions
NEET Chemistry QUESTION #7347
Question 1
Using Planck's constant \(h = 6.63 \times 10^{-34}\) Js and speed of light \(c = 3.0 \times 10^8\) ms\(^{-1}\), the wavelength (in metres) of a photon with frequency \(8 \times 10^{15}\) s\(^{-1}\) is closest to:
  • \(3 \times 10^7\) m
  • \(2 \times 10^{-25}\) m
  • \(5 \times 10^{-18}\) m
  • \(3.75 \times 10^{-8}\) m✔️
Correct Answer Explanation
Formula: \(\lambda = \dfrac{c}{\nu}\)

\(\lambda = \dfrac{3.0 \times 10^8}{8 \times 10^{15}} = 3.75 \times 10^{-8}\) m

This wavelength falls in the UV region of the electromagnetic spectrum. Always use \(\lambda = c/\nu\) for photon wavelength problems.