Duration: 2:19

1 views

0

Three of the fundamental constants of physics are the
\( \mathrm{P} \)
universal gravitational constant, \( \mathrm{G}=6.7 \times 10^{-11} \mathrm{~m}^{3} \mathrm{~kg}^{-1} \mathrm{~s}^{-2} \),
W
the speed of light, \( \mathrm{c}=3.0 \times 10^{8} \mathrm{~m} / \mathrm{s} \), and planck's constant, \( \mathrm{h}=6.6 \times 10^{-34} \mathrm{~kg} \mathrm{~m}^{2} \mathrm{~s}^{-1} \).
The energy of a photon is given by \( \mathrm{E}=\frac{\mathrm{hc}}{\lambda} \).
If \( \lambda=4 \times 10^{-7} \mathrm{~m} \), the energy of photon is
(A) \( 3.0 \mathrm{eV} \)
(B) \( 4.5 \mathrm{eV} \)
(C) \( 2.10 \mathrm{eV} \)
(D) \( 3.95 \mathrm{eV} \)


📲PW App Link - https://bit.ly/YTAI_PWAP
🌐PW Website - https://www.pw.live