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University Physics III

University Physics III · Nuclear and Particle Physics · 11.04

Q values, two-body kinematics, and conservation ledgers

Q from tabulated masses, the momentum-fixed energy split between two fragments of a parent at rest, lab-frame thresholds for endothermic reactions, and the charge, nucleon-number, and lepton-number ledgers that forbid reactions without predicting any rate.

Course-map guide · not a complete lesson or simulation

Scope & orientation

What this subsection covers

Q from tabulated masses, the momentum-fixed energy split between two fragments of a parent at rest, lab-frame thresholds for endothermic reactions, and the charge, nucleon-number, and lepton-number ledgers that forbid reactions without predicting any rate.

A strong response uses feynman-style interaction sketches 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

Does binding energy per nucleon computed from tabulated atomic masses locate the maximum of the curve and predict which reactions release energy?

Read the complete note

Does binding energy per nucleon computed from tabulated atomic masses locate the maximum of the curve and predict which reactions release energy? Useful evidence includes computed B/A across the nuclide chart, the nuclide that actually maximises it, Q values for one fission and one fusion reaction, and comparison with published energy releases.

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 claimQ values, two-body kinematics, and conservation ledgers

Q from tabulated masses, the momentum-fixed energy split between two fragments of a parent at rest, lab-frame thresholds for endothermic reactions, and the charge, nucleon-number, and lepton-number ledgers that forbid reactions without predicting any rate.

02 · RepresentationThe subsection's claim

Model, evidence, and boundary

03 · TestPrediction before measurement

What is the strongest test of a claim about Q values, two-body kinematics, and conservation ledgers?

04 · Evidence & boundaryDecide, then qualify

Does binding energy per nucleon computed from tabulated atomic masses locate the maximum of the curve and predict which reactions release energy?

Read the complete note

Does binding energy per nucleon computed from tabulated atomic masses locate the maximum of the curve and predict which reactions release energy? Useful evidence includes computed B/A across the nuclide chart, the nuclide that actually maximises it, Q values for one fission and one fusion reaction, and comparison with published energy releases.

Interactive diagram for Q values, two-body kinematics, and conservation ledgers: 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

What is the strongest test of a claim about Q values, two-body kinematics, and conservation ledgers?

Quick check

Test the reasoning, not recall

What is the strongest test of a claim about Q values, two-body kinematics, and conservation ledgers?

Choose an answer to test the model.