Question

What is the frequency of a wave having a period equal to 18 seconds? a. 6.6 × 10-2 hertz b. 5.5 × 10-2 hertz c. 3.3 × 10-2 hertz d. 1.8 × 10-2 hertz e. 8.0 × 10-3 hertz

Answer 1

Frequency = 1/period. ... 1 / 18 sec = (1/18) per sec. That's 0.056 per sec or 0.056 Hz. (rounded) (5.6 x 10^-2 Hz)

Answer 2

Answer: Option (b) is the correct answer.

Step-by-step explanation:

The time taken by a wave crest to travel a distance equal to the length of wave is known as wave period.

The relation between wave period and frequency is as follows.

`T = (1)/(f)`

where, T = time period

f = frequency

It is given that wave period is 18 seconds. Therefore, calculate the wave period as follows.

`T = (1)/(f)`

or,
`f = (1)/(T)`

=
`(1)/(18 sec)`

= 0.055 per second (1 cycle per second = 1 Hertz)

or, f =
`5.5 * 10^(-2) hertz`

Thus, we can conclude that the frequency of the wave is
`5.5 * 10^(-2) hertz`.