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Solve the numerical problem. The speed of light is 3 × 108 m/s. Calculate the frequency of red light of a wavelength of 6.5 × 10−7 m.

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Question

Solve the numerical problem.

The speed of light is 3 × 108 m/s. Calculate the frequency of red light of a wavelength of 6.5 × 10−7 m.

Sum
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Solution

Given: c = 3 × 108 m/s, λ = 6.5 × 10–7 m

To find: Frequency (ν)

Formula: c = νλ

Calculation: From formula,

ν = `"c"/λ=(3xx10^8)/(6.5xx10^-7)` = 4.6 × 1014 Hz

The frequency of red light is 4.6 × 1014 Hz.

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Chapter 13: Electromagnetic Waves and Communication System - Exercises [Page 241]

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Balbharati Physics [English] Standard 11 Maharashtra State Board
Chapter 13 Electromagnetic Waves and Communication System
Exercises | Q 3. (iii) | Page 241

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