A small object at rest, absorbs a light pulse of power $20 \mathrm{~mW}$ and duration $300 \mathrm{~ns}$. Assuming speed of light as $3 \times 10^{8} \mathrm{~m} / \mathrm{s}$, the momentum of the object becomes equal to :
Solution
<p>Assuming the small object as photon.</p>
<p>Momentum $(p)=\frac{E}{C}$</p>
<p>$=\frac{20\times10^{-3}\times300\times10^{-9}}{3\times10^8}$</p>
<p>$=2\times10^{-17}$ kg m/s</p>
About this question
Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect
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