The period of a sinusoid is the inverse of its frequency

Evidence

Since it is going around at constant speed, the motion of the ball starts to repeat itself after exactly one revolution. The time it takes to go one revolution is called the period T, and the motion we say is periodic with period T. T is a solution to the equation 2π fT = 2π, i.e., T = 1/f. The period is simply the inverse of the frequency. — Eric J. Heller, Why You Hear What You Hear- An…, 255

Categorization

Category: Definitional Content

  • DEFINE: Establishes the period-frequency relation T = 1/f, a foundational relation for all of acoustics.

Broader Connections