Title: POWER RUN
Purpose
To calculate the power generated by people.
Concept
Power is the rate of doing work. Power can be calculated by dividing the work done,
by the time it takes to do the work. Power is measured in watts (W). People
exert power in many situations, including lifting objects and climbing stairs.
Materials
Stopwatch, stairs, meter stick, calculator
Procedure
1. Measure (or convert - 1 kg = 2.2 lbs) and record the mass of the runner in kilograms.
2. Measure the height of one step and multiply by the number of steps to find the height of the staircase. Record.
3. Measure and record the time it takes the runner to quickly and carefully climb the stairs.
4. Repeat 2 more trials, and calculate the average time to climb the stairs.
Analysis
1. Calculate the weight of the runner in Newtons.
2. Calculate the work the runner did against gravity while climbing the stairs.
3. Calculate the power in watts using the average time.
4. Convert the power in watts to horsepower (1 hp = 746 watts).
5. How many 60 watt light bulbs could operate using the power calculated from the runner?
6. What fraction of a horsepower is your runner equal to?
7. If an economy car engine is 100 horsepower, how many people would it take to equal one engine?
