Length of Pendulum: Does COM Matter?

Click For Summary
SUMMARY

The length of a pendulum significantly influences its time period, as described by the equation T=2π√(L/g). Measuring the length from the center of mass (COM) of the pendulum bob, rather than the bottom, is crucial for accurate calculations. A simple pendulum with a length of 50 cm will exhibit the same time period as a 1-meter wooden ruler, provided the ruler is pivoted near its end. Understanding the role of the COM in pendulum mechanics is essential for precise timing in experiments.

PREREQUISITES
  • Understanding of pendulum mechanics
  • Familiarity with the formula T=2π√(L/g)
  • Knowledge of center of mass concepts
  • Basic principles of rotational dynamics
NEXT STEPS
  • Study the impact of varying lengths on pendulum time periods
  • Explore the concept of center of mass in different shapes
  • Investigate the effects of pivot points on pendulum motion
  • Learn about the applications of pendulum mechanics in real-world scenarios
USEFUL FOR

Physics students, educators, and anyone interested in the principles of pendulum motion and mechanics.

AnthroMecha
Messages
26
Reaction score
0

Homework Statement



Does it matter whether you measure the length of the pendulum to the center of mass of the ball or to the bottom of the ball


Homework Equations



T=2pi*root(L/g)


The Attempt at a Solution



I can see that L (length) is a factor, but I'm not sure why it matters if it's taken from the COM or not??

Any help is appreciated!
 
Physics news on Phys.org
It is essential! A simple pendulum (small mass on the end of a massless string) of length 50cm will have the same time period as a wooden ruler of length 100cm (1 metre).
The 1m ruler must be pivoted as near the end as possible.
The centre of mass of a uniform wooden ruler is at the middle (50cm mark)
 
Thank you! That clears it up perfectly.
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
5K
  • · Replies 32 ·
2
Replies
32
Views
3K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 6 ·
Replies
6
Views
4K
Replies
2
Views
1K
  • · Replies 15 ·
Replies
15
Views
2K
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 41 ·
2
Replies
41
Views
21K