Description
Two people can do the exact same amount of work — but only one of them is more “powerful.” What’s actually different between them? This video answers that question by defining power as the rate of doing work, building the average power equation, and then testing it against two worked examples: stopping a speeding car, and a stair-climbing comparison that separates work (which only cares about height) from power (which also cares about time).
✅ Define power as the rate at which work is done
✅ Calculate average power using P = ΔE/Δt = W/Δt
✅ Recognize alternate phrasings for power on the AP exam
✅ Explain why work depends on force, distance, and angle, but power also depends on time
⏱️ Timestamps
0:00 – Hook: same work, different power — what’s the difference?
0:51 – Quick review: work as ∫F·dr
1:15 – Defining power: P = ΔE/Δt
1:45 – AP exam phrasing: “rate of energy change,” “energy dissipated,” and more
2:31 – Worked example: Stop That Car!
2:51 – Work to stop a 1,500 kg car at 20 m/s: 3.0 × 10⁵ J
3:23 – Average power to stop it in 3 s: 100 kW
3:44 – Worked example: Work vs. Power with Joe on the stairs
4:09 – Which climb requires the most work?
5:10 – Which climb uses energy the fastest?
6:09 – Bridge to instantaneous power
This video is part of the MasteryFlip approach to AP Physics C — watch, take notes, then come to class ready to work problems together. Curious about the MasteryFlip Framework? Check out the ReachEveryStudent Podcast, new episodes every Monday at reacheverystudent.com.