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Homework Help: Physics Help Please

  1. Jul 28, 2006 #1
    I would like to inquire the help with a few physics problems :surprised : THERES NO WORK BECAUSE I HAVE NO CLUE WHERE TO START. SOMEONE TELL ME WHERE TO BEGIN PLEASE. :

    1. A grappling hook, attached to a 1.5m-rope, is whirled in a circle that lies in the vertical plane. The lowers point on this circle is at the ground level. The hook is whirled at a constant rate of three revolutions per second. In the absence of air resistance, to what maximum height can the be cast?

    2. At a carnival, you can try to ring a bell by striking a target with a 9.00-kg hammer. in response, a 0.400-kg metal piece is sent upward toward the bell, which is 5.00m above. Suppose that 25.0% of the hammer's kinetic energy is used to do the work of sending the metal piece upward. How fast must the hammer be moving when it strikes the target so that the bell just barely rings?

    3. A motorcycle (mass of cycle plus rider = 250kg) is traveling at a steady speed of 20.0 m/s. The force of air resistance acting on the cycle and rider is 200N. Find the power necesary to sustain this speed if (a) the road is level and (b) the road is sloped upward at 37 degrees with respect to the horizontal.
    Last edited: Jul 28, 2006
  2. jcsd
  3. Jul 28, 2006 #2


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    1. can you find the speed that the hook is moving while it is being whirled?
    2. how much kinetic energy does it take to move the piece high enough to hit the bell?
    3. what is the definition of power?
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