Question about simple harmonic motion

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Homework Help Overview

The discussion revolves around a problem involving simple harmonic motion (SHM) in the context of a torsional oscillator. A square block is mounted on an axle and connected to a spring, raising questions about the period of oscillation when the block is rotated and released.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore the nature of the problem as a torsional oscillator, discussing the concept of restoring torque and its relation to rotational inertia. Questions arise regarding the calculation of the period and the distinction between different angular frequencies involved.

Discussion Status

Some participants have offered insights into the equations governing the motion, including the relationship between torque and angular displacement. There is ongoing clarification regarding the parameters involved, such as the moment of inertia and the spring constant, with no explicit consensus reached yet.

Contextual Notes

Participants are navigating the complexities of the problem, including the need to define the restoring torque and its implications for the oscillation period. The discussion highlights potential confusion over the parameters and their roles in the equations of motion.

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A square block, with a mass of 3.40 kg and edge lengths d = 6.00 cm, is mounted on an axle through its center. A spring of spring constant k = 1190 N/m connects the block's upper corner with a rigid wall. Initially the spring is at its rest length. If the block is rotated by 3° and then released, what is the period of the resulting SHM?

What type of problem should this be treated as?
 
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It oscillates by rotation ... it's called a torsional oscillator.
You look at "restoring torque" which returns the object
(which responds slowly due to its rotational Inertia) to
the equilibrium orientation angle.

set torque = I alpha , get torque as function of theta.
Now it should operationally look like an oscillator eq'n.

Be careful to keep the omega_(orientation_change_rate)
distinct from the omega_(forward trig function argument)
omega_ocr has amplitude 3 degrees, while
omega_tfa is multiplied by time.

Enjoy it, this one is fun!
 
there are two different omegas? I'm slightly confused. I know for a torsion oscillator, period is usually found using T = (2*pi)*(I/kappa)^(1/2)
Inertia can be calculated...but how should I go about getting kappa, setting the net torque = -k*theta?
 
Torque is force multiplied by perpendicular distance from axis of rotation.

Tau = -K(d/2)^2 @ sin@ =@ approx
 

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