How Do You Calculate Maximum Angular Acceleration of a Pendulum?

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To calculate the maximum angular acceleration of a simple pendulum with a mass of 0.25kg and a length of 1m, use the formula α = -g/L * sin(θ), where g is 9.8 m/s² and θ is the angle of displacement. The maximum angular acceleration occurs at the bottom of the swing when the pendulum is at its maximum displacement. Given a displacement of 15 degrees, convert this angle to radians for calculation. By substituting the values into the equation, the maximum angular acceleration can be determined. This approach effectively combines concepts of torque, moment of inertia, and forces acting on the pendulum.
UrbanXrisis
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I am given that the mass of a simple pendulum is 0.25kg, length 1m and displaced 15 degrees then released. How would I find the max angular acceleration?

I could calculate max velocity with conservation of energy, but not sure now to calculate the max acceleration.
 
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UrbanXrisis said:
I am given that the mass of a simple pendulum is 0.25kg, length 1m and displaced 15 degrees then released. How would I find the max angular acceleration?

I could calculate max velocity with conservation of energy, but not sure now to calculate the max acceleration.

Maximum acceleration occurs where the force is maximum, at the ends of the motion. Find the unbalanced force acting on the mass at the point of release, and use Newtons second law. The forces acting are gravity and the tension in the string. The question asks for angular acceleration, so you will need to convert from linear acceleration to angular acceleration.

As an alternative, if you know about torque and moment of inertia of the mass on the string, you can calculate angular acceleration from that point of view.
 


To find the maximum angular acceleration of a simple pendulum, we can use the equation: α = -g/L * sin(θ), where α is the angular acceleration, g is the acceleration due to gravity (9.8 m/s²), L is the length of the pendulum, and θ is the angle of displacement.

In this case, we have all the necessary values except for the angle of displacement. We can use the given information that the pendulum is displaced 15 degrees and released to find the value of θ.

Once we have the value of θ, we can plug it into the equation to find the maximum angular acceleration of the pendulum. It is important to note that the maximum angular acceleration will occur at the bottom of the pendulum's swing, when it is at its maximum displacement.

In summary, to find the maximum angular acceleration of a simple pendulum with a mass of 0.25kg, length of 1m, and displaced 15 degrees, you can use the equation α = -g/L * sin(θ), where θ is the angle of displacement at the bottom of the pendulum's swing.
 
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