A wave has a frequency of 1000 Hz and a wavelength of 0.2 m. What is its speed?
Answer and explanation
Correct answer: B. 200 m/s
- Step 1: Wave speed v = fλ. Step 2. v = 1000 × 0.2 = 200 m/s. Answer: 200 m/s. Why not the others: 5000 m/s is what you get if you divide frequency by wavelength. 1000.2 m/s is what you get if you add the numbers. 0.0002 m/s is what you get if you divide wavelength by frequency.
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