Before discussing the Second pendulum, let’s first discuss the simple pendulum.
We all might have seen a simple pendulum.
In which a small diameter bob is connected through a long thread with tension
, that has very small mass.
Now, when we swing it, it moves to and fro along the same line.
When objects move to and fro along a same line, then that type of motion is called simple harmonic motion.
Hence, this pendulum is executing a simple harmonic motion.
And the time period of oscillations (T) of the pendulum will be calculated as,
Now, we are ready to know about the second pendulum.
Let’s discuss the second pendulum.
Seconds pendulum were used in vintage clocks, which is advanced in one second.
It takes a time duration of one seconds to reach the bob of a seconds pendulum from one extreme to other extreme position.
Now, the pendulum reaches at its extreme position twice in one oscillation.
Hence, the time period of seconds pendulum will be two seconds.
Therefore, the second pendulum can be defined as the pendulum with a time period of two seconds.
Now, we can calculate the length of the pendulum by using the expression,
Here, the time period and acceleration due to gravity for second pendulum is known.
Hence, after putting the value,
Hence, the length of pendulum in the seconds pendulum is
The second pendulums were used in vintage clocks, which is advanced in one second.
And the time period of second pendulum is two seconds.
So, the second pendulum can be defined as the pendulum with an oscillation period of two seconds.
Since, the time period is known. So, we can calculate the length easily which will be,