Recent content by enrijuan

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    What is the optimal speed for a box to slide down a roof with minimal friction?

    ah ok so then my original equation is correct? as in W= \DeltaKE + PE ? mu(9.81cos20)(5.1)= -.5vi2 + (9.81)(5.1sin20) ? or should I find the Net Force as JesseC said? If I take that route then Fx=f-Fgx right? Fx=mu(m)(g)-m(g)(sin20) Fx=.54(2.1)(9.81cos20)-2.1(9.81sin20)= 3.41 N Fx= 3.41=...
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    What is the optimal speed for a box to slide down a roof with minimal friction?

    I thought that there would be force due to gravity, normal force and the force due to kinetic friction? and I drew a diagram and thought that the distance was directly below as in the y-axis and the hypotenuse would be the displacement.
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    What is the optimal speed for a box to slide down a roof with minimal friction?

    Homework Statement You and your friend Peter are putting new shingles on a roof pitched at 20\circ . You're sitting on the very top of the roof when Peter, who is at the edge of the roof directly below you, 5.1 m away, asks you for the box of nails. Rather than carry the 2.1 kg box of nails...
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    Static and kinetic friction involving velocity

    wow thank you so much! thanks for the welcome, the µ, the help, and above all the patience!
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    Static and kinetic friction involving velocity

    then, .5(7)(0)-.5(7)(2.3^2)= (.250)(7)(-9.81)d ? then d=1.08 meters ?
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    Static and kinetic friction involving velocity

    oh the end velocity is goin to be zero right? so, 1/2mvf2-1/2mvi2=W 1/2mvf2-1/2mvi2 = (µmg)(d) is this right?
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    Static and kinetic friction involving velocity

    so, work done= (7.00 kg)(2.3 m/s) + 0? then work done =18.515 J then 18.515=(force due to kinetic friction)(distance)?
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    Static and kinetic friction involving velocity

    doesnt the conservation of mechanical energy talk about potential and kinetic energy? I don't understand how I would get potential energy or how work would help me in the problem.
  9. E

    Static and kinetic friction involving velocity

    I know that force over distance is work but I don't see how that would help me in this problem... I am sorry I am having a hard time with this one... I also know that d= vt
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    Static and kinetic friction involving velocity

    Homework Statement A baggage handler drops your 7.00 kg suitcase onto a conveyor belt running at 2.30 m/s. The materials are such that µS= 0.410 and µK= 0.250. Homework Equations How far is your suitcase dragged before it is riding smoothly on the belt? The Attempt at a Solution...
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