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Silly question for fun

  1. Nov 22, 2012 #1
    My friend bought a new chair for the living room. He says I sit in it with too much force and claims I basically free fall into the chair (padded chair, like a one person loveseat) and we tried to calculate the pounds per second against the chair but I don't know much about material science and the construction of chairs to withstand anything. The chair is about 1/3meter from my postiere and we got about 1700 lbs of force but I do know that's distributed over my toosh, plus I have knees and make it not exactly a free fall and im 180 lbs. Its just for fun and I know where and tear happens eventually but is it something to worry about?
  2. jcsd
  3. Nov 23, 2012 #2
    I'm not quite sure what your question is but the amount of force that is acting on the chair due to your weight is approximately 800N. I'm not sure how you got 1700lb (which is roughly 7600N.) The formula to find the force of gravity is: Fg = mg. Where m is the mass of the object in kg and g is the gravitational field strength of whatever is causing the gravitational attraction. For the earth, this is 9.8 [itex]\frac{N}{kg}[/itex]. Gravitational field strength in other words is the acceleration due to gravity, so it can be stated as 9.8 m s-2.
  4. Nov 23, 2012 #3
    Well, there is no simple answer for this question. As you accelerate due to gravity field, you gain momentum, wich you lose during the impact with the chair, in some time interval. The average force that you excert on the chair can be calculated by dividing the gained momentum with the impact duration (remember the definition of force : Δp/Δt)
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