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Physics · PYQ NEET UG 2020
हिन्दीLight with an average flux of \( 20\text{ W/cm}^2 \) falls on a non-reflecting surface at normal incidence having surface area \( 20\text{ cm}^2 \). The energy received by the surface during time span of \( 1\text{ minute} \) is
Correct answer · Option 2
\( 24 \times 10^3\text{ J} \)
Explanation
Energy \( E = (\text{Flux}) \times A \times t = 20\text{ W/cm}^2 \times 20\text{ cm}^2 \times 60\text{ s} = 24000\text{ J} = 24 \times 10^3\text{ J} \).
