Question

An object that completes 100 vibrations in 5 seconds has a period of

Answer 1

Answer: None of the above choices are correct.

Explanation:

Here we are talking about the vibration frequency of an object:

$f=\frac{100vibrations}{5s}$ (1)

The frequency  $f$ is defined as the inverse of the period $T$ (time):

$f=\frac{1}{T}$ (2)

Therefore the Period is:

$T=\frac{1}{f}$ (3)

Now, if we want to find the period we have to substitute equation (1)  in equation (3):

$T=\frac{1}{\frac{100}{5s}}$

$T=\frac{5s}{100}$

Finally:

$T=0.05s$ >>>>This is the value of the period, which does not match with any of the options given.

Hence:

None of the above choices are correct.

Answer 2

Answer:

The correct answer is D) None of the above choices are correct.

Explanation:

We know that the object completes 100 vibrations in 5 seconds.

The period (T) is the time in which an object or a particle realizes a complete vibration (oscillation).

The period is the inverse of the frequency.

The unit of the period are the seconds.

The period can be calculated using the following equation :

$T=\frac{Time}{NumberOfVibrations}$

In this exercise :

$T=\frac{5s}{100}$

$T=0.05s$

Therefore, the correct answer is D)