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University Physics II

University Physics II · Magnetic Fields and Magnetic Forces · 8.04

Velocity selectors

Crossed electric and magnetic fields, force balance, selected speed, direction, field tolerances, and device limitations.

Course-map guide · not a complete lesson or simulation

Scope & orientation

What this subsection covers

Crossed electric and magnetic fields, force balance, selected speed, direction, field tolerances, and device limitations.

A strong response uses torque-versus-angle graphs 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

Which electric and magnetic field settings transmit only a chosen particle velocity?

Read the complete note

Which electric and magnetic field settings transmit only a chosen particle velocity? Useful evidence includes vector equations, trajectory simulations, parameter sweeps, transmission windows, and analytic comparison.

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. Departments may redistribute weeks, laboratory hours, optics, or the modern-physics survey to match local requirements. This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. Departments may redistribute weeks, laboratory hours, optics, or the modern-physics survey to match local requirements. Thermal physics appears as an unnumbered institutional extension: some universities assess it within Physics II, while others teach it in a separate course, so include the thermal extensions only where the local syllabus requires them. 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 claimVelocity selectors

Crossed electric and magnetic fields, force balance, selected speed, direction, field tolerances, and device limitations.

02 · RepresentationThe subsection's claim

Model, evidence, and boundary

03 · TestPrediction before measurement

When should a model used for Velocity selectors be revised?

04 · Evidence & boundaryDecide, then qualify

Which electric and magnetic field settings transmit only a chosen particle velocity? Useful evidence includes vector equations, trajectory simulations, parameter sweeps, transmission windows, and analytic comparison.

Interactive diagram for Velocity selectors: 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 Velocity selectors be revised?

Quick check

Test the reasoning, not recall

When should a model used for Velocity selectors be revised?

Choose an answer to test the model.