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InformationUDP datagram service

UDP exchanges addressed messages without adding reliable stream delivery.

DefinitionInformationDNS names, records and caching

DNS distributes typed resource records through a delegated naming hierarchy.

DefinitionInformationCombinational digital-circuit model

A combinational output depends on current valid inputs after a bounded settling delay.

ModelInformationBoolean gates and truth tables

Logic gates compute Boolean functions with truth values 0 and 1.

DefinitionInformationClocked storage and sequential state

Sequential circuits retain state, so current inputs alone do not determine their behavior.

ModelInformationStored programs and instruction sets

Stored instructions control computation through a specified hardware/software interface.

ModelPhysicsDisplacement, distance and average speed

Displacement compares endpoints; distance measures the travelled path.

ModelPhysicsConstant-acceleration kinematics

Closed formulas require constant acceleration over the interval.

ModelPhysicsInertial reference frames and inertia

Newtonian force balances need an inertial frame or explicit inertial terms.

ModelPhysicsCircular motion and centripetal acceleration

A constant speed can still have an acceleration.

ModelPhysicsMass, gravitational weight and apparent weight

Mass is in kilograms; gravitational weight is a force.

ModelPhysicsNormal forces and tension

Contact geometry determines the force direction.

ModelPhysicsFree-body diagrams and system boundaries

List forces on the selected body once.

ModelPhysicsStatic and kinetic dry friction

Static friction is a responsive force with an approximate limit.

ModelPhysicsFluid drag and terminal speed

Terminal speed depends on the chosen drag model.

ModelPhysicsImpulse and momentum transfer

Time-integrated net force changes momentum.

ModelPhysicsElastic and inelastic collisions

Momentum conservation and kinetic-energy conservation are different.

ModelPhysicsConservative forces and potential energy

Potential-energy differences encode path-independent work.

ModelPhysicsMechanical-energy conservation and dissipation

Mechanical energy is only part of the total energy.

ModelPhysicsHooke’s spring model and elastic energy

A linear spring restores displacement toward equilibrium.

ModelPhysicsMechanical power

Power measures the rate of work or energy transfer.

ModelPhysicsRigid-body rotational kinetic energy

Rotation stores kinetic energy determined by mass distribution.

ModelPhysicsRolling without slipping

No slip constrains velocity at the contact point.

ModelPhysicsStatic equilibrium and torque balance

Zero net force alone does not prevent rotation.

ModelPhysics · Earth & cosmosYoung, shear and bulk elastic moduli

Stress and strain need a loading geometry and a constitutive range.

ModelPhysicsDensity and fluid pressure

Density is mass per volume; pressure is normal force per area.

ModelPhysicsAbsolute, gauge and differential pressure

A zero gauge reading need not be a vacuum.

ModelPhysicsPascal’s principle and ideal hydraulics

A pressure change is transmitted; pressure need not be equal at different heights.

ModelPhysicsNewtonian viscosity and Poiseuille flow

Viscosity relates shear stress to velocity gradient.

ModelPhysics · ChemistrySurface tension and capillary rise

Interface forces can support pressure jumps and capillary columns.

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Impulse and momentum transfer

Physics

Time-integrated net force changes momentum.

Key knowledge

For a constant-mass Newtonian particle in an inertial frame, linear momentum is p=mv and net-force impulse over an interval is J=∫F_netdt=p_f−p_i. For a fixed many-particle system, the external impulse changes total momentum when internal force pairs cancel. A large collision force over a short time is governed by the impulse, not force magnitude alone.

Values and equations

p=mv; J=∫_(t_i)^(t_f)F_net(t)dt=Δp

p,J,Δp
Momentum, net impulse and momentum change kg m s⁻¹
m
Constant mass kg
v
Vector velocity m s⁻¹
F_net
Vector net force N
t_i,t_f,t
Interval endpoints and time s

Conditions and scope

  • The particle/system and time interval must be fixed and all applicable external forces included.
  • Neglecting external impulse in a collision is an approximation to justify; an individual colliding object’s momentum is not generally conserved.
Sources · 2

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. Samuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University, University Physics (2016)2 sources
    1. University Physics Volume 1, §9.1: linear momentumSamuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University, University Physics (2016)Textbook chapteropenstax.orgRead source
    2. University Physics Volume 1, §9.2: impulse and collisionsSamuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University, University Physics (2016)Textbook chapteropenstax.orgRead source

Evidence and review

Read §9.1 linear-momentum definition and §9.2 impulse definition9.3 and impulse–momentum theorem9.6. Many-particle clause reuses the already scoped conservation record.

2026-10-10 · /root/audit_life_earth_chemistry — independent Chemistry/Life/Earth editor. Independent AI editorial review of this entry's statements, equations, applicability conditions and source coverage. Source checks apply to these claims within their stated limits.

Related reference entries

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Showing 1–3 of 3 relationships

Scientific relationships · 3 / 3

The relationship type describes the connection. Its linked statements, sources and conditions define the scope.

  1. Uses definition
    Relationship sources · 2

    Linked statements

    • For a constant-mass Newtonian particle in an inertial frame, linear momentum is p=mv and net-force impulse over an interval is J=∫F_netdt=p_f−p_i. For a fixed many-particle system, the external impulse changes total momentum when internal force pairs cancel. A large collision force over a short time is governed by the impulse, not force magnitude alone.

    This relation concerns the stated impulse and momentum transfer claim and its conditions; it does not assert an unqualified prerequisite or an additional theorem.

  2. Uses definition
    Relationship sources · 2

    Linked statements

    • For a constant-mass Newtonian particle in an inertial frame, linear momentum is p=mv and net-force impulse over an interval is J=∫F_netdt=p_f−p_i. For a fixed many-particle system, the external impulse changes total momentum when internal force pairs cancel. A large collision force over a short time is governed by the impulse, not force magnitude alone.

    This relation concerns the stated impulse and momentum transfer claim and its conditions; it does not assert an unqualified prerequisite or an additional theorem.

  3. Derived from
    Relationship sources · 1

    Linked statements

    • For a dilute classical ideal gas with isotropic molecular velocities in its rest frame, elastic wall collisions transfer momentum and give pV=Nm⟨v²⟩/3. Combining this with pV=Nk_BT gives mean translational kinetic energy m⟨v²⟩/2=3k_BT/2 and rms speed √⟨v²⟩=√(3k_BT/m). The rms speed is distinct from the mean speed and the net drift velocity.

    The idealized wall pressure follows time-averaged momentum transfer in elastic molecular collisions.

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