Human Power
Purpose:
To determine the power output of a person.
Equipment:
- 2 Two-meter Meter Sticks
- 1 Stopwatch
- 1 Kilogram-bathroom Scale
- Humans
Introduction:
Power is defined to be the rate at which work is done or equivalently, the rate at which
energy is converted from one form to another. In this experiment you will do some work
by climbing from the first floor of the science building to the second floor. By measuring
the vertical height climbed and knowing your mass, the change in your gravitational
potential energy can be found:
∆ PE = mgh
Where m is the mass, g the acceleration of gravity, and h is the vertical height gained.
Your power output can be determined by
Power =
∆ PE ,
∆t
where ∆t is the time to climb the vertical height h.
Procedure: (from lab handout)
1. Determine your mass by weighing on the kilogram bathroom scale. Record your mass in kg..
2. Measure the vertical distance between the ground floor and the second floor for the science
building. This can most easily be done by using two meter long metersticks held end to end in the
stairwell at the west end of the building. Make a careful sketch of the stairwell area that explains
the method used to determine this height.
3. Designate a record keeper and a timer for the class. At the command of the timing person, run or
walk (whatever you feel comfortable doing) up the stairs from the ground floor to the second
floor. Be sure that your name and time are recorded by the record keeper.
4. After everyone in the class has completed one trip up the stairs, repeat for one more trial.
5. Return to class and calculate your personal power output in watts using the data collected from
each of your climbing trip up the stairs. Obtain the average power output from the two trials.
'
6. Put your average power on the board and then calculate the average power for the entire class once
everyone has reported their numbers on the board.
7. Determine your average power output in units of horsepower.
No comments:
Post a Comment