Question

What is the formula for frequency?

Answer 1

Hint: Frequency can be defined as the number of occurrences of an event that is repeating, in a unit time. The SI unit of frequency is Hertz (Hz). The occurrence of one repeating event in a second is given by Hertz (Hz).

Complete answer: We know that frequency is defined as the number of vibrations or cycles per unit of time. It is denoted either by the Greek letter $\nu$ or by $$$$.
Frequency can also be defined from the equation that defines the relationship between time period and frequency.
Time period (T) can be defined as the time taken to complete one cycle of a repeated occurrence.
The relation between time period and frequency is given by
$$={\displaystyle \frac{1}{T}}$$
We know that the SI unit of frequency is Hertz. Since Hertz is defined as one occurrence of an event that is repeating per second, the base SI unit of frequency is $s^{-1}$ and has the dimensions $T^{-1}$.
Now, the frequency of a repeating event can be calculated by dividing the number of times the event occurs by the time taken for that number of events to occur.
For example, the heart of a newborn baby beats at the rate of 120 beats per minute. This can also be written as 120 beats in 60 seconds. Hence, the frequency will be given as
$$={\displaystyle \frac{120}{60}}=2Hz$$
So, the frequency at which a newborn baby's heartbeats is 2Hz.

Note: It should be noted that in wave propagation, the relation between wavelength and frequency, in a vacuum, can be given by
$$\nu ={\displaystyle \frac{c}{\lambda }}$$
Where $\nu$ is the frequency, $\lambda$ is the wavelength and c is the speed of light.