Electric power explained: P = VI, I²R and V²/R, watts and kilowatt-hours, with worked examples.
Electrical theory for apprentices: size the circuit, predict the heat, estimate the energy.
Electrical engineering by EPA:
Power is the rate at which electrical energy is converted into heat, light or motion. This video shows why a resistor heats up, where P = VI comes from, the watt as a joule per second, the I²R and V²/R forms, a worked 2.4 kW kettle example, heat lost in the cable, kilowatt-hours, why I²R doesn’t give a motor’s power (and where power factor comes in), and how power ratings drive decisions on the job.
CHAPTERS
0:00 Why power matters
0:18 Why a resistor warms up
0:41 Collisions make heat
0:52 Where P = V × I comes from
1:09 The watt
1:26 P = I²R and V²/R
1:41 Example: a 2.4 kW kettle
1:54 Heat in the cable
2:16 Kilowatt-hours
2:33 Limits: motors and power factor
2:58 Power on the job
3:15 Recap
PowerLab Training (sign-in required):
RESOURCES MENTIONED / CREDITS
• The Engineering Mindset: video on power factor (“Power Factor Explained – The basics”), YouTube. Search for it by name.
ABOUT ELECTRICAL PROJECTS AUSTRALIA (EPA)
PowerLab Training is made by Electrical Projects Australia, electrical engineers for critical infrastructure, based in Newcastle NSW since 1991. We work with owners, developers, builders and operators from design through to energisation.
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Narration: synthetic (AI-generated) voice. Animation and script: PowerLab Training, Electrical Projects Australia (epa.energy).
Disclaimer: This video is general training information only. It is not a substitute for the current editions of AS/NZS 3000, AS/NZS 3008 and other applicable standards, your local regulations, or the instruction of your RTO/TAFE. Always refer to the current standards and your RTO/TAFE.
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