Number of photons of equal energy emitted per second by a 6 mW laser source operating at 663 nm is ____.
(Given : h=6.63×10−34 J.s and c=3×108 m/s)
Held on 28 Jan 2026 · Verified 6 Jul 2026.
2×1016
10×1015
5×1015
5×1016
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