Question

A bicycle wheel rotates uniformly through 2.0 revolutions in 4.0 s. what is the frequency of the wheel's rotation?

Answer 1

The frequency is defined as the number of cycles done in one second:
$f= \frac{N}{t}$
where N is the number of cycles and t is the time taken to complete N cycles. The wheel in this problem does N=2 revolutions in a time of t=4.0s, therefore its frequency of rotation is: 
$f= \frac{N}{t} = \frac{2.0}{4.0s} = 0.5 Hz$

Answer 2

Answer: The frequency of the wheel's rotation is 0.5 Hz.

Explanation:

Frequency of rotation: It is defined as the number of revolution in a second.

The expression for the frequency in terms of the number of revolution in a given time is as follows;

$f=\frac{N}{t}$

Here N is the number of cycles and t is the time taken.

Put N= 2 rev and t= 4 s in the above expression.

$f=\frac{2}{4}$

$f=0.5 Hz$

Therefore, the correct answer is 0.5 Hz.