“Mastering the Simple Pendulum: Discover the secrets of Time and Motion”

Avr 8, 2025

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par

Rajansmoorthy

dans PHYSICS, NEET, JEE, EDUCATION

Simple Pendulum Experiment

Simple Pendulum Experiment : Introduction

The simple pendulum experiment is a well-known physics experiment that helps understand the relationship between a pendulum’s length and time period. It also provides a method for figuring out the acceleration due to gravity(g).This experiment provides a fundamental understanding of oscillatory motion and aids in verifying theoretical predictions with empirical observations.

Simple Pendulum Experiment : Objective

The objective of the simple pendulum experiment is to:

Examine the relationship between a simple pendulum’s length L and time period T.

Find the effective length of a second’s pendulum. as well as 

To calculate the laboratory’s acceleration caused by gravity.

Simple Pendulum Experiment : Materials Required

A small pendulum bob (say 18 mm metallic sphere)

A light inextensible string (about 1.5 m long)

A rigid stand with clamp

A split rubber cork

A stop watch or a stop clock

A meter scale

A marker or chalk (to mark the equilibrium position)

Simple Pendulum Experiment : Formula

Simple pendulum Experiment : Theory

A light, inextensible string suspends a small, dense bob, which is allowed to oscillate around its mean position in a simple pendulum. The purpose of the experiment is to examine the relationship between the pendulum’s length (L) and time period (T).

Simple pendulum Experiment : Procedure

Setting up the experiment:

Hang the bob and use a split rubber cork to firmly connect one end of the rope to the clamp.

Attach the metal bob to the other end.

Make sure the bob is not touching anything and is hanging freely.

Determine the Length of Effectiveness: Using a metre scale, find the distance between the split rubber cork’s bottom and the bob’s center.

Change the pendulum’s length L in increments of 60, 70, 80, etc.  

Determine the time period T for each length by timing 20 oscillations.  

Make a table with the observations.  

Plot L against T and L against T^2  

Measuring the time period(T): 

How long it takes the pendulum bob to complete one oscillation is known as the time period.

Pull the bob slightly by.about 5 to 10 degrees away from the vertical position.Without using any force, gently release it so that it starts oscillating around the mean position.

Start the stopwatch when it crosses the equilibrium position after a few oscillations are complete.

It is necessary to count 20 full oscillations, or one full cycle from side to side and back.Divide the total time by 20 to find the length of a single oscillation.

Simple pendulum Experiment: Observations and Calculations

Simple pendulum Tabular Column:

Mean value of L /T^2

Mean value of L /T2 is  0.2454 ms^-2

Acceleration Due to Gravity in the Laboratory

Simple pendulum Experiment: L-T^2 graph

Simple pendulum L-T^2 graph

Calculation of effective length of second’s pendulum

A second’s pendulum is a basic pendulum with a two-second time period (T = 2s). With one second required to travel from one extreme to the other and another second required to return, this shows that a complete oscillation takes two seconds.

Simple pendulum Experiment:Conclusion

A useful tool for precisely measuring time is a second’s pendulum.

When the length approaches 99 cm, the time period stays around 2 seconds.

The link between length and time period in a basic pendulum is also confirmed by this experiment.

T2 is proportional to L, as seen by the L-T^2 graph’s straight line.  

A second’s pendulum’s effective length is roughly 98.30 cm, which is near to the theoretical value.  

Using pendulum motion, this experiment aids in the precise determination of g.  

Percentage error 1.01%

Simple pendulum Experiment- Precautions

Oscillations are affected by air resistance.

Air resistance can be reduced by using a small, heavy bob.  

Inaccurate pendulum length measurement.  

Time measurement mistake due to human error( (human reaction time when the stopwatch is started or stopped).

LINKS TO OTHER PHYSICS EXPERIMENTS

Principle of moments

Helical spring experiment

Speed of sound with air column magic