What is the Difference Between Frequency and Period?

Frequency and period are distinct yet related quantities associated with waves, including sound waves, light waves, and ocean waves. The key differences between them are:

1. Definition: Frequency refers to how often something happens, such as the number of vibrations or cycles per unit time. Period refers to the time it takes for something to happen, such as the time required to complete one cycle or vibration.
2. Nature: Frequency is a rate quantity, measuring the number of cycles occurring in a specific amount of time. Period is a time quantity, measuring the duration of time needed to complete one cycle.
3. Units: Frequency is measured in cycles per second, also known as Hertz (Hz). Period is measured in seconds per cycle.
4. Relationship: Frequency and period are inversely proportional to each other. If the period is doubled, the frequency is halved, and vice versa. The relationship between frequency and period can be expressed as:$$f = \frac{1}{T}$$ or $$T = \frac{1}{f}$$where 'f' is the frequency and 'T' is the period.

For example, if a wave has a frequency of 2 Hz (2 cycles per second), it means that each cycle takes 0.5 seconds (1 second / 2 cycles). In this case, the period of the wave is 0.5 seconds.

Comparative Table: Frequency vs Period

The difference between frequency and period can be summarized in the following table:

To better understand the difference between frequency and period, consider the example of a pendulum. The frequency of the pendulum's swings represents the number of swings per unit of time, while the period is the time it takes for one complete swing. These two concepts are related, with frequency being inversely proportional to the period.