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Homework Help: Constant force

  1. Dec 15, 2009 #1
    A barrel of oil with a mass of 65 kg is rolled down a 1.2 m ramp. Due to a constant force exerted on it, the barrel reaches a velocity of 4.2 m/s just on leaving the ramp. Find the constant force on the barrel while it is on the ramp and express your answer in the form of a sentence relating force, change in velocity, distance, and direction.

    what would the formula be for this question? :\

    Mass: 65kg
    Velocity: 4.2m/s
    acceleration: 1.2m x 9.81m/s = 11.77m/s
  2. jcsd
  3. Dec 15, 2009 #2


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    This question isn't answerable without additional information. Are you sure you copied the question correctly?
  4. Dec 15, 2009 #3
    I did copy it right, I copied and pasted the question from the assignment I was given, what kind of information is missing?
  5. Dec 15, 2009 #4


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    I agree the problem is a little vague. It's plausible that the force is just the force of gravity.
  6. Dec 15, 2009 #5


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    Right. In that case, this question becomes simple.

    How much kinetic energy did the object gain in going down the ramp? Considering that W=Fd and you know d, what's F?
  7. Dec 15, 2009 #6
    it didnt give you an angle?

    then you could calculate both the force of gravity and the force of the object rolling down the incline?

    You can use this formula (very basic)


    your answer should be in newtons.

    im not sure though but maybe that velocity is just information to mislead you???

    Edit: never mind. but the force exerted on the y-direction can still be found with that
    Last edited: Dec 15, 2009
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