Wave Motion - Mission WM2 Detailed Help

A wave is moving through a medium. A point on the medium is undergoing many up and down oscillations in a short amount of time. This is conclusive evidence that the wave has a relatively large ____.

To be successful at this question, you must know the definition of the various wave quantities: frequency, period, speed, wavelength, and amplitude. A wave involves the repeated and periodic vibration of a medium. As each particle of the medium undergoes its up and down (or back and forth) vibration, the familiar wavelike pattern is established in the medium. This question is describing how often a point on the medium is vibrating up and down. The question is clearly not describing any quantity pertaining to length or distance, which rules out amplitude and wavelength as possible choices. It states that a point (and thus all the points) on the medium undergoing a large number of vibrations in a short amount of time. You must determine what wave quantity describes the number of vibrations per unit of time.

Many students confuse the speed of a wave with the frequency of a wave. Both are time-based quantities. But don't be fooled! The speed of a wave is the distance traveled by a point on the wave pattern per unit of time. The frequency of a wave refers to the number of back-and-forth vibrational cycles that a point on the medium makes per unit of time. Speed refers to how fast the wave travels and frequency refers to how often a point on the medium repeats its vibration.