The frequency of electromagnetic wave, which best suited to observe a particle of radius 3 × 10⁻⁴ cm is of the order of (a) 10¹⁵ (b) 10¹⁴ (c) 10¹³ (d) 10¹²

Answer: (b). To observe a particle, the wavelength should be of the order of its size. λ ≈ 3×10⁻⁴ cm = 3×10⁻⁶ m. ν = (c)/(λ) = 3×10⁸3×10⁻⁶ = 10¹⁴ Hz. So the answer is (b) 10¹⁴ Hz.

The frequency of electromagnetic wave, which best suited to observe a… | NEET 1991 (AIPMT)

Q46NEET 1991 · AIPMTMedium

Electromagnetic Spectrum & Atmosphere

The frequency of electromagnetic wave, which best suited to observe a particle of radius $3 \times 10^{-4}\text{ cm}$ is of the order of

Show answer and solution

Answer: (b)

To observe a particle, the wavelength should be of the order of its size.
$\lambda \approx 3\times10^{-4}\ \text{cm} = 3\times10^{-6}\ \text{m}$ .
$\nu = \dfrac{c}{\lambda} = \dfrac{3\times10^{8}}{3\times10^{-6}} = 10^{14}\ \text{Hz}$ .
So the answer is (b) $10^{14}$ Hz.

Report a mistake

Electromagnetic Spectrum & Atmosphere question from NEET 1991 (AIPMT)

More questions on Electromagnetic Spectrum & Atmosphere