Two simple harmonic waves having equal amplitudes of 8 cm and equal frequency of 10 Hz are moving along the same direction. The resultant amplitude is also 8 cm. The phase difference between the individual waves is _________ degree.
Answer (integer)
120
Solution
$A_{R}=\sqrt{A_{1}^{2}+A_{2}^{2}+2 A_{1} A_{2} \cos \phi}$
<br/><br/>
$$
\begin{aligned}
& 8=\sqrt{8^{2}+8^{2}+2 \times 8 \times 8 \cos \phi} \\\\
& \Rightarrow \cos \phi=-\frac{1}{2} \\\\
& \Rightarrow \phi=120^{\circ}
\end{aligned}
$$
About this question
Subject: Physics · Chapter: Waves · Topic: Wave Motion and Types
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