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A source produces monochromatic light of frequency \(5.0\times {10}^{14}Hz\) and the power emitted is 3.31 mW. The numbe…

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A source produces monochromatic light of frequency \(5.0\times {10}^{14}Hz\) and the power emitted is 3.31 mW. The number of photons emitted per second by the source, on an average is

a

\({10}^{16}\)

b

\({10}^{24}\)

c

\({10}^{10}\)

d

\({10}^{20}\)

✓ Correct answer: a)

\({10}^{16}\)

Explanation

The energy of a single photon is given by the formula \(E=h\nu\) ,where \(h\) is Planck's constant. The value of Planck's constant is

\(h=6.626\times10^{-34}J\cdot s\).

\( E=(6.626\times10^{-34}J\cdot s)(5.0\times10^{14}Hz) \)

\( E=3.313\times10^{-19}J \)

Step 3: Calculate the number of photons emitted per second

The number of photons emitted per second, N, is the total power divided by the energy of a single photon.

\( N=\frac{P}{E} \)

\( N=\frac{3.31\times10^{-3}W}{3.313\times10^{-19}J} \)

\(N\approx9.99\times10^{15}\text{ photons/s} \)

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