MCQ
The displacement of the interfering light waves are ${y_1} = 4\sin \omega \,t$ and ${y_2} = 3\sin \left( {\omega \,t + \frac{\pi }{2}} \right)$. What is the amplitude of the resultant wave
- ✓$5$
- B$7$
- C$1$
- D$0$
✓
Answer
Correct option: A.
$5$
a
(a) Since $\phi = \frac{\pi }{2}$ ==> $A = \sqrt {a_1^2 + a_2^2} = \sqrt {{{(4)}^2} + {{(3)}^2}} = 5$
(a) Since $\phi = \frac{\pi }{2}$ ==> $A = \sqrt {a_1^2 + a_2^2} = \sqrt {{{(4)}^2} + {{(3)}^2}} = 5$
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