Two point sources are simultaneously creating waves with a wavelength of 6 cm. Point X lies between the two sources. It is 9 cm from one source and 15 cm from the other. What wave heights do you expect at point X? A. The waves will never get very high or low. B. The waves may get very high, but will never get very low. C. The waves may get very low, but will never get very high. D. The waves will sometimes get very high and very low.

OPTION D (The waves will sometimes get very high and very low) is the answer.

Explanation:

Wavelength = velocity ÷ frequency

As the frequency which measures the number of waves per unit of time is inversely proportional to the wavelength, point X which lies between two sources, and one source is shorter than another, the wave heights at point x will vary as the distances from point X vary too. This means that waves at point X depending on the wave type and source will get very high at times and very low.