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University Physics III

University Physics III · Oscillations · 1.06

Simple and physical pendulums

Gravity as a restoring torque, d²θ/dt² = −(Mgd/I)sin θ, the small-angle step that makes it harmonic, T = 2π√(I/(Mgd)) and T = 2π√(L/g), the centre of oscillation, and the θ₀²/16 correction showing isochronism is only first order.

Course-map guide · not a complete lesson or simulation

Scope & orientation

What this subsection covers

Gravity as a restoring torque, d²θ/dt² = −(Mgd/I)sin θ, the small-angle step that makes it harmonic, T = 2π√(I/(Mgd)) and T = 2π√(L/g), the centre of oscillation, and the θ₀²/16 correction showing isochronism is only first order.

A strong response uses energy-versus-displacement parabolas and states where the model stops being reliable.

Reasoning checklist

Evidence, assumptions and limits

01

Assumptions to state

State the system, observable, approximation, and conditions held fixed before using a model.

02

Evidence to collect

How do the damping constant and the drive frequency reshape steady-state amplitude, phase lag, and the time the transient takes to die away?

Read the complete note

How do the damping constant and the drive frequency reshape steady-state amplitude, phase lag, and the time the transient takes to die away? Useful evidence includes numerically integrated trajectories, an amplitude-versus-frequency sweep at several damping values, a phase-versus-frequency sweep tested against the π/2 crossing at ω₀, fitted peak positions and widths, and comparison with the linear-response prediction.

03

Limits to state

This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus.

Read the complete note

This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. Third-semester content is the least standardised of the introductory sequence: departments place oscillations, waves, optics, and thermal physics differently, and the modern-physics units here are a bounded survey rather than a complete course in relativity, quantum mechanics, atomic, nuclear, or particle physics. Follow your institution's published scope, notation, laboratory programme, and assessment rules. A result should be checked against units, signs, limiting cases, and the conditions under which its model was derived.

Diagram & examples

Work the claim before choosing an equation

Interactive concept map

Follow the model from claim to evidence.

01 · Physical claimSimple and physical pendulums

Gravity as a restoring torque, d²θ/dt² = −(Mgd/I)sin θ, the small-angle step that makes it harmonic, T = 2π√(I/(Mgd)) and T = 2π√(L/g), the centre of oscillation, and the θ₀²/16 correction showing isochronism is only first order.

02 · RepresentationThe subsection's claim

Model, evidence, and boundary

03 · TestPrediction before measurement

When should a model used for Simple and physical pendulums be revised?

04 · Evidence & boundaryDecide, then qualify

How do the damping constant and the drive frequency reshape steady-state amplitude, phase lag, and the time the transient takes to die away?

Read the complete note

How do the damping constant and the drive frequency reshape steady-state amplitude, phase lag, and the time the transient takes to die away? Useful evidence includes numerically integrated trajectories, an amplitude-versus-frequency sweep at several damping values, a phase-versus-frequency sweep tested against the π/2 crossing at ω₀, fitted peak positions and widths, and comparison with the linear-response prediction.

Interactive diagram for Simple and physical pendulums: follow the physical claim through its representation, proposed test, evidence, and model boundary.

modelModel, evidence, and boundary turns the stated idea into a representation that can make a prediction.

Example questions

Try the reasoning before revealing the structure.

Diagram check

When should a model used for Simple and physical pendulums be revised?

Quick check

Test the reasoning, not recall

When should a model used for Simple and physical pendulums be revised?

Choose an answer to test the model.