JEE Mains · Physics · STD 11 - 14. waves and sound
Two harmonic waves moving in the same direction superimpose to form a wave \(\mathrm{x}=\mathrm{a} \cos (1.5 \mathrm{t}) \cos (50.5 \mathrm{t})\) where \(t\) is in seconds. Find the period with which they beat (close to nearest integer)
- A 6 s
- B 4 s
- C 1 s
- D 2 s
Answer & Solution
Correct Answer
(D) 2 s
Step-by-step Solution
Detailed explanation
The given equation can be written as \(\mathrm{x}=\frac{\mathrm{a}}{2} \cos [1.5+50.5] \mathrm{t}+\frac{\mathrm{a}}{2} \cos [50.5-1.5]\) \(x=\frac{a}{2} \cos [52 t]+\frac{a}{2} \cos [49 t]\) Here, \(2 \pi \mathrm{f}_1 \& 2 \pi \mathrm{f}_2=49\)…
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