1.

22. Two simple harmonic motions are represented by the equations \( y_{1}=10 \sin \left(3 \pi t+\frac{\pi}{4}\right) \) and \( y_{2}=5(3 \sin 3 \pi t+\sqrt{3} \cos 3 \pi t) \). Their amplitudes are in the ratio ofa. \( \sqrt{3} \)b. \( 1 / \sqrt{3} \)C. 2d. \( 1 / 6 \)

Answer»

Given,

y1 = 10 sin (3πt + \(\frac{\pi}{4}\))

y2 = 5 (3 sin3πt + \(\sqrt 3\) cos3πt)

y2 = 15 sin3πt + \(5\sqrt 3\) cos3πt

Amplitude of y1 is A1 = 10

Amplitude of y2 is A2\(\sqrt{(15)^2+(5\sqrt3)^2}\)

A2\(\sqrt{225+(8.6)^2}\)

A2\(\sqrt{225+73.96}\)

A2\(\sqrt{298.96}\)

A2 = 17.29

Then ratio of amplitude is :

\(\frac{A_1}{A_2}\) \(\frac{10}{17.29}\)

\(\frac{A_1}{A_2}\) = \(\frac{1}{\sqrt 3}\) 

Hence, 

Option (b) is correct.



Discussion

No Comment Found

Related InterviewSolutions