- Build and operate the assigned VEX winch.
- Measure the required load, lift distance, and lift time.
- Calculate work, power, and efficiency using your test data.
POE Unit 1 • Lesson 1.8
Work, Power, and Efficiency in Mechanical Systems
Focus question: How do work, power, and efficiency help engineers evaluate a mechanical system?
Start Here
What You Need to Do
Use this section as your checklist before moving through the lesson resources below.
- Completed winch build
- Work, power, and efficiency data sheet
Your winch completes the required lift and your calculations use measured data with correct units.
Mission Briefing
Today’s Plan
A focused lesson sequence that builds toward the VEX Cargo Lift Engineering Challenge.
Opening promptConcept voteAerospace linkCompare optionsEvidence challengeQuick checkExit ticket
Lesson Targets
What You Will Be Able to Do
I can calculate work, power, and efficiency using measured input and output data from a mechanical system.
Work, power, and efficiency data sheet
Work, power, and efficiency are calculated from matching input/output data and interpreted as performance evidence.
Activity Flow
How the Lesson Moves
This page highlights the lesson elements you need for practice, evidence, and submission.
1. Define one test cycle
Use the same load movement for input and output measurements.
2. Calculate work and power
Use force, distance, and time with correct units.
3. Evaluate efficiency
Compare useful output work with supplied input work and explain losses.
Lesson Interactive
Calculate Work, Power, and Efficiency
A motor mechanism applies 30 N over 2.0 m in 4.0 s. The useful output work is 48 J. Complete the performance analysis.
Trial Data
30 NInput force
2.0 mInput distance
4.0 sTime
48 JUseful output work
Calculations
Use W = Fd, P = W/t, and efficiency = output work ÷ input work × 100.
Today’s Work
Main Deliverable
Work, Power, and Efficiency Data Sheet
Analyze one mechanism trial using measured or provided data.
- Show input work, output work, power, and efficiency calculations.
- Identify one likely energy loss and one revision that could reduce it.
Exit Ticket
Mission Debrief
One way today’s lesson connects to an aerospace mechanism or VEX rover system.
One type of evidence you could use to support a design decision.
One question you still have about mechanisms, energy, power, or the Unit 1 challenge.
Resources
Lesson Resources
Principles of Engineering
Return to the POE course hub for units, resources, certifications, and current course information.
VEX Cargo Lift Engineering Challenge
Use this unit project context when connecting the lesson to mechanism planning, testing, and design review evidence.