Work as energy transfer

Interactive lesson
When a force does work, and when it doesn'tInteractive lesson
Work is energy transferredInteractive lesson
Why perpendicular forces do no workInteractive lesson
Positive or negative workInteractive lesson
What negative work meansInteractive lesson
Calculate the signed work done by one forceInteractive lesson
Solve the work equation for force or distanceInteractive lesson
Only the parallel component worksInteractive lesson
Calculate work for an angled forceInteractive lesson
Work done by or on a systemInteractive lesson
Net work from several forces

Kinetic and gravitational potential energy

Interactive lesson
The kinetic energy relationInteractive lesson
How speed changes kinetic energyInteractive lesson
How mass changes kinetic energyInteractive lesson
Solve the kinetic energy equation for speed or massInteractive lesson
Rank objects by kinetic energyInteractive lesson
Lifting stores energyInteractive lesson
The gravitational potential energy relationInteractive lesson
The reference level is a free choiceInteractive lesson
Solve the GPE equation for height or massInteractive lesson
Height, not path, sets the GPE change

Springs and elastic potential energy

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Why the path doesn't matter for GPEInteractive lesson
More stretch needs more forceInteractive lesson
The spring constantInteractive lesson
Hooke's lawInteractive lesson
Apply Hooke's lawInteractive lesson
Spring constant from a force-extension graphInteractive lesson
Stored energy as the area under the force-extension graphInteractive lesson
The elastic potential energy relationInteractive lesson
How stretch changes stored energyInteractive lesson
Solve the elastic potential energy equation

The work-energy theorem and the conservation law

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The work-energy theoremInteractive lesson
Why net work shows up as kinetic energyInteractive lesson
Find the speed change from the net workInteractive lesson
Find the force or distance behind a kinetic energy changeInteractive lesson
Mechanical energy definedInteractive lesson
Total mechanical energy at an instantInteractive lesson
Conservation of mechanical energyInteractive lesson
Is mechanical energy conserved here?Interactive lesson
Fastest and slowest points on a path

Energy charts, diagrams and conservation solves

Interactive lesson
Read an energy bar chartInteractive lesson
Construct an energy bar chartInteractive lesson
Spot the flaw in an energy bar chartInteractive lesson
Read a potential energy diagramInteractive lesson
Turning points on a potential energy diagramInteractive lesson
Find a speed using energy conservationInteractive lesson
Find the height or starting speed neededInteractive lesson
Spring launch problemsInteractive lesson
Multi-stage energy chain

Power and the energy ledger

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Who transfers energy faster?Interactive lesson
Power and the wattInteractive lesson
Calculate power from work and timeInteractive lesson
Solve the power equation for work or timeInteractive lesson
Power from force and speedInteractive lesson
Why power is force times speedInteractive lesson
Calculate power from force and speedInteractive lesson
Find the force or the speed from the powerInteractive lesson
Where the energy goes: dissipationInteractive lesson
Calculate the energy dissipatedInteractive lesson
The total energy stays constantInteractive lesson
Where kinetic energy goes in an inelastic collisionInteractive lesson
Calculate the kinetic energy converted in a collisionInteractive lesson
Conservation solves with friction