Power Equation
Reference from the original Physics I textbook.
- Power Equation
Average power: P_avg = ΔW/Δt. Instantaneous power: P = dW/dt = F⃗ · v⃗.
1 watt = 1 J/s; 1 joule = 1 N·m = 1 kg·m²/s²; 1 newton = 1 kg·m/s².
- Related Glossary Terms
- Index
Reviewed physics notes (2)
These corrections keep the original lesson’s purpose while fixing errors in the source edition.
- Source incorrectly labels a joule as N·s. — Reference 1
- Finite work over time is average power. — Reference 1
Glossary and deeper reading · 2 refreshers
These editorial refreshers supplement the reading. Definitions and examples are added guidance; original source wording and recorded answers remain in their original context.
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Power
Power is the rate at which energy is transferred or converted. It is measured in watts, with one watt equal to one joule per second. For example, two motors can lift the same load through the same height but have different average powers if they take different times.
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Mechanical work
Mechanical work is energy transferred by a force through displacement of its point of application. For a constant force on a particle, it depends on the force component along the particle’s displacement, and it can be positive, negative, or zero. For example, a magnetic force perpendicular to a particle’s displacement does zero work on that particle.