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?
Lv 7
? a posé la question dans Science & MathematicsMathematics · il y a 1 décennie

Easy (?) Physics Problem?

Sally applies a horizontal force of 462 N with a rope to drag a wooden crate across a floor with a constant speed. The rope tied to the crate is pulled at an angle of 56.0° and Sally moves the crate 24.5 m. What work is done by the floor through the force of friction between the floor and the crate?

3 réponses

Pertinence
  • Anonyme
    il y a 1 décennie
    Réponse favorite

    W=Fs cos x

    ...=462*24.5*cos 56=462*24.5*0.5592=6329.585J

  • Anonyme
    il y a 1 décennie

    Im sure there's a physics section, please ask in that section next time.

    Horizontal component of Sally's force = 462 cos(56 deg) = 258N

    Friction = 258N (as the crate is moving at a constant speed i.e. no net force)

    Work = Fd = 258 x 24.5 = 6330 J (3 sig fig)

  • ?
    Lv 4
    il y a 5 ans

    The penny's pace relies on how a lot mass the arena has "gravity"... Now as soon as the penny is dropped it'll start to fall with a steady acceleration relative to the mass the arena the penny is falling to, has. pace = (acceleration) * 369.... or whatever like that. I'm to lazy to uncover the exact "gravitational" pull of earth.

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