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प्रश्न
Find the energy of photon which have momentum 2 × 10-16 gm-cm/sec.
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उत्तर
Given, P = `2 × 10^(−16)` gm−cm/sec; c = 3 × 1010 cm/sec
E = pc
= 2 × 10−16 × 3 × 1010
= 6 × 10–6 erg
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