How to Measure G with a Compound pendulum

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SUMMARY

This discussion focuses on measuring acceleration due to gravity (g) using a compound pendulum, specifically constructed from a steel rod. The formula T=2*Pi*sqrt(I/(m*g*L)) is critical, where T represents the period of oscillation, I is the moment of inertia, m is mass, g is acceleration due to gravity, and L is the distance from the pivot to the center of mass. Key steps include measuring the period, determining the mass, locating the center of mass, and calculating the moment of inertia, which is essential for accurate results.

PREREQUISITES
  • Understanding of pendulum mechanics
  • Familiarity with moment of inertia calculations
  • Ability to measure mass and distance accurately
  • Knowledge of oscillation periods
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  • Research how to calculate the moment of inertia for various shapes
  • Learn about the principles of oscillation in rigid bodies
  • Explore methods for accurately locating the center of mass
  • Investigate advanced pendulum experiments to measure gravitational acceleration
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Students in physics, educators teaching mechanics, and anyone conducting experiments related to gravitational measurements and pendulum dynamics.

rossildosil
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For my Advanced Higher Physics Investigation i am measuring acceleration due to gravity. Having already done it with a simple pendulum my teacher says i have to do the same with a "Compound Pendulum". I was wondering how to do this and also how to make a compound pendulum with a steel rod.

Many thanks Ross.
 
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A compound pendulum is one where the rod is not massless, and may have extended size; that is, an arbitrarily shaped rigid body swinging by a pivot. In this case the pendulum's period depends on its moment of inertia I around the pivot point.

T=2*Pi*Sqrt(I/(m*g*L)) where I is the moment of inertia of the rod and L is the distance from the pivot to the center of mass. Measure the period and mass. Locate center of mass and measure distance to pivot. Determining moment of inertia could be the tricky part.
 
Hi that's great. Sorry for the slow reply, but i need to clear something up. Is the T the time taken for one oscilation?

Thanks
 
T is the period or how long to complete one complete cycle
 

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