Work–energy theorem
Net work W = ΔEk = ½mv² − ½mv₀²; a cart pulled by constant force on a track.
Work & mechanical energyWork, kinetic/potential energy, and conservation.
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Work–energy theorem
Work–energy theorem: net work equals change in kinetic energy, W = ΔEk = ½mv² − ½mv₀². A cart is pulled by a constant force on a horizontal track.
Net work equals change in kinetic energy: W = ΔEk = ½mv² − ½mv₀².
Key formulas
W_\text{合}=\Delta E_kW=(F-f)x\Delta E_k=\tfrac12 mv^2-\tfrac12 mv_0^2
How to use
- Set force F, mass m, friction μk, and initial speed v₀.
- Watch the cart accelerate and track W and ΔEk readouts.
- Verify that W always equals ΔEk.
Applications
- Work–energy theorem: Net work equals change in kinetic energy: W = ΔEk = ½mv² − ½mv₀².
- Classroom focus: a cart pulled by constant force on a track.
FAQ
How is friction work calculated?
Friction does negative work Wf = −f·x; net work W = (F − f)·x equals the change in kinetic energy.
What does MVP mean on this page?
An interactive sketch with formulas and parameters. Polished Ready labs are the full bench experience.
What does the “Work–energy theorem” lab practice?
Tune parameters and match readouts to the “Work–energy theorem” relations — useful for prep and demos.
Is force always along velocity?
No. Net force aligns with acceleration; velocity can point elsewhere.