Question

The modes in a material having a V number of 20 is (a) 20 (b) 400 (c) 200 (d) 100 I got this question in a national level competition. I want to ask this question from Properties of Waveguides topic in portion Waveguides of Electromagnetic Theory Select the correct answer from above options Electromagnetic Theory questions and answers, Electromagnetic Theory questions pdf, Electromagnetic Theory question bank, Electromagnetic Theory questions and answers pdf, mcq on Electromagnetic Theory pdf,electromagnetic theory book pdf,electromagnetic theory pdf notes,electromagnetic theory lecture notes,electromagnetic theory of light,maxwell electromagnetic theory,electromagnetic theory proposed by,electromagnetic theory engineering physics,electromagnetic theory nptel

Answer 1

Correct answer is (c) 200 Easiest explanation: The relation between the modes and the V number is given by m = v^2/2. Given that v = 20, we get m = 20^2/2 = 200 modes.