Question

The length of the simple pendulum which ticks seconds is:
A. 0.5m
B. 1m
C. 1.5m
D. 2m

Answer 1

Hint: Meaning of word tick second is 2 second. Recall the formula of a simple pendulum and its concept. Consider day to day life examples to understand simple pendulum like bob tighten at one end of thread.

Complete Step-by-Step solution:
A pendulum is a weight suspended from a table so that it can freely swing.
To solve the question we need to first understand the question, what question is saying to us and after that what we have to calculate?
By knowing these two things it will be easy for us to solve the question.
In the given question, word ticks are used which means the time period of a simple pendulum is 2 second.
i.e. T = 2 second --------------------(1)
Formula of simple pendulum is given by,
$T=2\pi \dfrac{\sqrt{l}}{\sqrt{g}}$
Where,
T is the time period of simple pendulum
l is the length of thread or wire or string
g is the acceleration due to gravity
Put value of equation one in above equation, we get
$2=2\pi \sqrt{\dfrac{l}{g}}$
To solve further, square on both sides
We get,
$4=4{{\pi }^{2}}\times(\dfrac{l}{g})$
Rearrange the equation,
$l=\dfrac{g}{{{\pi }^{2}}}$
$l=\dfrac{9.8}{{{\pi }^{2}}}$
$l=0.99m$
Which is approximately equal to 1m
I.e. 1m
The length of the simple pendulum which ticks seconds is 1m.
Correct option is (B)

Note: Always predict what should be output. Focus on data given in question. It is just a simple pendulum. Do not get confused between oscillation, harmonics, beat, and simple pendulum. Pendulum cannot be considered a free fall body.