Question

Three waves of equal frequency having amplitudes 10mm, 4mm and 7mm arrive at a given point with successive phase difference $\pi/2$ . The amplitude of the resulting wave in mm is given by

• A. 7
• B. 6
• C. 5
• D. 4

Answer 1

Answer: (C)

5

Answer 2

$a_{res} = \sqrt{a^2_1 + (a_2 - a_3)^2}$