Equal wavelength waves of amplitude 0.24 m and 0.16 m interfere with one another.What is the resulting minimum amplitude that can result?

A) 0.16 m
B) 0.08 m
C) 0 m
D) −0.4 m
E) 0.20 m

Question

Equal wavelength waves of amplitude 0.24 m and 0.16 m interfere with one another.What is the resulting minimum amplitude that can result?
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A) 0.16 m
B) 0.08 m
C) 0 m
D) −0.4 m
E) 0.20 m

Quizplus · Accepted Answer

When two waves interfere with each other, the resulting amplitude at a given point is the algebraic sum of the individual amplitudes. In this case, the waves have equal wavelength but different amplitudes.

When the waves are in phase (crests aligned with crests and troughs aligned with troughs), their amplitudes add up to give a maximum amplitude of 0.24 m + 0.16 m = 0.4 m.

When the waves are completely out of phase (crests aligned with troughs), their amplitudes subtract to give a minimum amplitude of 0.24 m − 0.16 m = 0.08 m.

Therefore, the resulting minimum amplitude that can result is 0.08 m, which corresponds to choice B.

Equal Wavelength Waves of Amplitude 0