A wave has speed 340 m/s and frequency 850 Hz. Its wavelength is
A{'text': '0.25 m', 'label': 'A'}
B{'text': '0.40 m', 'label': 'B'}
C{'text': '2.5 m', 'label': 'C'}
D{'text': '4.0 m', 'label': 'D'}
Answer & Solution
Correct answer: B. {'text': '0.40 m', 'label': 'B'}
1. Wave equation: v = f × λ, where f is frequency and λ is wavelength.
2. Rearrange: λ = v / f.
3. λ = 340 / 850 = 0.40 m.
4. This is a typical wavelength for sound in air at 850 Hz.
_Source: NCERT Class 11 Physics, Ch 14 "Waves", §14.4_
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