'I'Il'l'lE ['0 Hlll'l : S 4. Repeat the experiment with the other person. it is good to have another person do the lab. so you can compare their data to your date so you get a good understanding of Human Power. 5. Calculate the amount of'power that was produced in traveling up the flight of stairs For both walking and running. To calculate the Power, follow these steps. Power = Work Done / Time Data Needed: Weight {in Pounds) = lbs. Now take you weight in pounds and convert it to Newtons, these are the force units for the metric system. 1 pound = 4.448 N, so input your weight in pounds into the equation below and multiply your weight in pounds by 4.448 to get your weight in Newtons. Weight {in Newtons) = Weight in lbs. x [4.443 N I 1 lbs] lbs [4.448 N f llbs.) = N Now to calculate you work, input your Weight [in N] and the height of your climb (in m}. multiply those two together and you will get the work you did climbing the stairs. The units for work are Joules (J). This will be the same work for both walking and running, the difference will be when you calculate the power you produce. Work = Weight I Displacement = N x m Work = Weight x Displacement N X m Work = Joules Now to get the Power your produced, walking and running, you will take the work you did to climb the stairs or hill and divided that work by the time. So Power = Work / time. Since we are dividing the work (in J) by time (in seconds) we get the units of Watts for the Power you produced. Power walk = Joules / seconds = Watts Powerrun = Joules / seconds = WattsTo convert to horsepower, we need to convert. we just need to take your Power you produced in Watts and divided it by T46, this is our conversion method, since 1 horse power is equal to 746 Watts. So plug in your Power for walking up the stairs or hill and divided it by T46. repeat for the Power you produced running up the stairs or hi1]. Powers-so = 1Watts ( 112:) = Hp _ 1 HF _ PDWCrrun Watts ( T46 w ) Hp What you have learned about power and how it applies to you and the world around you. Keep in mind the questions listed below, Questions I. Does everyone produce the same power? 2 Why do you think the power produced was different? 3. Did you pmduce the same power walking as running, why'? 4 Does the person running up the steps have to touch every step? Why or why not? Stair Climb - Power of Humans Theory Average power is defined as the rate at which work is done or as the rate at which energy is transformed. ? =ayera e wer= workdone = energy transformed g P0 time time When people discuss the idea ofpower, the notion is that the power is how fast something is done. This is not always the case; the term horsepower came from the amount of work that a horse could do in one clay. Today people like to use the term horsepower to describe how powerful their car is, believing this defines a fast car; this may not be so. A 25f] horsepower car will always lose a race to a ltl horsepower motorcycle; why is this so? A motorcycle has much less mass then a car, so the motorcycle does not have to do the same amount of work that the car does. Therefore the energy transferred by the motorcycle to the ground, from the engine, is less than the amount of energy transferred to the ground, from the engine, for the car. What about humans, can they produce the power of a horse or a car? This lab you will investigate the power ofa human. Procedures I. Find a staircase or a slight hill which you will be asked to run and walk up, in general going from one floor in your house or apartment, to another floor is best}, i.e. the ground floor to the first floor. Determine the displacement, label and record the displacement. Use a ruler to measure one step, then count the number of steps and multiple the number of steps by the height of one step. Do this in meters. Displacement of Stairs = m 2. Get someone to help you time yourself, begin by walk up the ight of stairs, while the other person times how long it takes to walk the flight of stairs. Record the time. YOU CAN USE THE HANDBAILS Se TAKE MORE THEN ONE STEP ATA TIME! Time to Walk = seconds 3. Now record the time it takes to run up the flight of stairs. Time to Run = seconds