The momentum of a photon of an electromagnetic radiation is 3.3 × 10⁻²⁹ kg ms⁻¹. What is the frequency of the associated waves? [ h = 6.6 × 10⁻³⁴ Js; c = 3 × 10⁸ ms⁻¹ ] (a) 1.5 × 10¹³ Hz (b) 7.5 × 10¹² Hz (c) 6 × 10³ Hz (d) 3 × 10³ Hz

Answer: (a). p = hν/c ⇒ ν = pc/h ν = (3.3 × 10⁻²⁹)(3 × 10⁸)6.6 × 10⁻³⁴ = 1.5 × 10¹³ Hz So the answer is (a).

The momentum of a photon of an electromagnetic radiation is 3.3 ×… | NEET 1990 (AIPMT)

Q47NEET 1990 · AIPMTEasy

Photons: Energy, Momentum & Radiation Pressure

The momentum of a photon of an electromagnetic radiation is $3.3 \times 10^{-29}\text{ kg ms}^{-1}$ . What is the frequency of the associated waves?

[ $h = 6.6 \times 10^{-34}\text{ Js}$ ; $c = 3 \times 10^{8}\text{ ms}^{-1}$ ]

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Answer: (a)

$p = \frac{h\nu}{c} \Rightarrow \nu = \frac{pc}{h}$
$\nu = \frac{(3.3 \times 10^{-29})(3 \times 10^{8})}{6.6 \times 10^{-34}} = 1.5 \times 10^{13}\text{ Hz}$
So the answer is (a).