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Homework Help: Speed and Power from the energy content of one M&M candy

  1. Oct 4, 2016 #1
    1. The problem statement, all variables and given/known data

    I would like to know how fast one M&M could make me run.
    One M&M can provide about 12600 J of energy, I weight 68.5 kg.

    1)Does this mean I COULD run at about 19 m/s for a fraction of a second using Ke equation?
    (I know the human body is complex, muscles are about 25% efficient)

    2) I would like to calculate my NEGATIVE work in joules from raising in my hand a 1kg mass, 1m height

    3) How many M&M's would I have to eat to raise this?

    4) If I want to do question #2 in one second what variable do I need to know to calculate how many M&M's I would need

    2. Relevant equations


    P= mass*gravity*distance/time


    3. The attempt at a solution

    1) 19 m/s solving for velocity not factoring muscle efficiency or other variables
    2) -9.8 joules
    3) -9.8/12600=.0008
    4) ???

    Thanks!!! I am trying to design a lab for kids.
  2. jcsd
  3. Oct 4, 2016 #2

    Simon Bridge

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    Science Advisor
    Homework Helper

    A detailed calculation would require information about your metabolism.
    More general - you can look up the rate energy gets burned by "a human" in different activities ... this will tell you how long the energy of 1m&M would last ... however, not all the food you eat goes into the specific work you want to do, so a lot depends on how energy is distributed in your body.

    Your body also has a top speed based on it's mechanics and the environment you run in ... you can imagine your body being like running a large ship, an oceanliner or a capital ship like a destroyer or cruiser. There are lots of places the energy running bits of the ship can come from, and lots of places for it to be used. In extremis, energy can be diverted from some system to run others ... but it does not matter how much energy you put into just pushing the ship through the water, there is a max acceleration and a max speed that is possible.

    If you eat a very great deal of m&ms - it won't make you go faster unless you are already starved (and then, you'd have to wait a bit to recover).
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