Question

Non-digital clocks(which are becoming rarer) have a second hand that rotates around in a regular and repeating fashion. The frequency of rotation of a second’s hand on a clock is …. $Hz$.

• A. $\frac{1}{60}$
• B. $\frac{1}{12}$
• C. $\frac{1}{2}$
• D. $1$

Answer 1

The correct option is A

$\frac{1}{60}$

1. A second hand completes one rotation in $1$ a minute.
   We know that $1$ minute $=60$ seconds.
2. We know that frequency is the number of rotations completed in one second.

Find the frequency

1. We can use the rule of proportions to find the frequency as follows,
2. In $60$ seconds, the number of rotations $=1$,
3. So $1$ second, the number of rotations$=f(?)$
4. So,$f=\frac{1\times 1}{60}=\frac{1}{60}Hz$

So, the correct option is (a) $\frac{1}{60}$