Physics · 2021
JEE Main · 3 August 2021, Shift 2 · Q21
\ \ \ \ × 10^-10 J (joule) energy is contained in a 120 m length of a laser beam operating at 4 mW.
\_\_\_\_ $\displaystyle \times 10^{-10} \mathrm{~J}$ (joule) energy is contained in a $\displaystyle 120$ m length of a laser beam operating at $\displaystyle 4$ mW .
Official answer
16
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.