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A bulb is emitted electromagnetic radiation of $660 \mathrm{~nm}$ wavelength. The total energy of radiation is $3 \times 10^{-18} \mathrm{~J}$. The number of emitted photons will be
$\left(h=6.6 \times 10^{-34} \mathrm{~J} \mathrm{~s}, c=3 \times 10^8 \mathrm{~m} / \mathrm{s}\right)$
Options:
$\left(h=6.6 \times 10^{-34} \mathrm{~J} \mathrm{~s}, c=3 \times 10^8 \mathrm{~m} / \mathrm{s}\right)$
Solution:
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Verified Answer
The correct answer is:
$10$
Number of photons emitted $=n$
$\begin{aligned} & E=\frac{n h c}{\lambda} \\ & 3 \times 10^{-18}=\frac{6.6 \times 10^{-34} \times 3 \times 10^8 \times n}{660 \times 10^{-9}} \\ & n=\frac{30}{3}=10\end{aligned}$
$\begin{aligned} & E=\frac{n h c}{\lambda} \\ & 3 \times 10^{-18}=\frac{6.6 \times 10^{-34} \times 3 \times 10^8 \times n}{660 \times 10^{-9}} \\ & n=\frac{30}{3}=10\end{aligned}$
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