A wave of amplitude 20mm has intensity Ix. another wave of the same frequency but of amplitude 5mm has intensity Iy. What is Ix/Ty?
Correct answer: C. 16
- A. 2
- B. 4
- C. 16
- D. 256
Explanation
The intensity of a wave is proportional to the square of its amplitude. Therefore, if a wave has an amplitude of 20 mm and an intensity of I, and another wave has an amplitude of 5 mm and an intensity of I/4 (since the amplitude is one-fourth), then the ratio of their intensities is:I/(I/4) = 4INow, if another wave of the same frequency but of twice the amplitude (i.e., 40 mm) is considered, then its intensity would be:(40/20)^2 * I = 4ITherefore, the ratio of the intensity of this wave to the intensity of the 20 mm amplitude wave is:(4I)/(I) = 4Similarly, the ratio of the intensity of this wave to the intensity of the 5 mm amplitude wave is:(4I)/(I/4) = 16As it is numerical, it can have only one answer.
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Progressive waves transfer energy through oscillations, with wavelength, frequency, amplitude and wave speed related by v = fλ; sound speed depends on the medium. Superposition produces interference and stationary waves in strings and organ pipes, while simple harmonic motion describes the oscillation itself and must be distinguished from wave propagation.
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