When frequency is increased in a material with a given velocity, what happens to the wavelength?

When the frequency of a wave is increased while the velocity of the wave in the material remains constant, the wavelength must decrease. This relationship is described by the fundamental wave equation:

Wavelength (λ) = Velocity (v) / Frequency (f)

In this equation, if the velocity (v) does not change and the frequency (f) increases, the resulting wavelength (λ) must decrease to maintain the equality. This behavior underpins many applications in nondestructive testing (NDT) and ultrasonics, where adjustments to the frequency of the ultrasonic waves directly influence the wavelength, impacting resolution and penetration capabilities in material assessment.

Therefore, when frequency increases in a material with constant velocity, the wavelength accordingly decreases, leading to the correct answer.