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A 250W bulb emit light of wavelength 19.6nm. Find the no of electron emitted per second
A 250W bulb emit light of wavelength 19.6nm. Find the no of electron emitted per second
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To simplify calculations, you can use the value $hc \approx 1240 \text{ eV}\cdot\text{nm}$. Convert Power to eV/s first ($250 \text{ J/s} = 250 / (1.6 \times 10^{-19}) \text{ eV/s}$). Then $n = \text{Total Energy in eV} / \text{Energy of one photon in eV}$.
Updated On: Apr 21, 2026
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