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Homework Help: Physics 12 Journal help, please!

  1. Jan 19, 2009 #1
    Hey, any ideas/input would be very helpful! Thanks!

    1. It is sometimes said that water is removed from clothes during the spin cycle by centrifugal force throwing the water outward. Explain if this is correct by describing what centrifugal force is and how the spin cycle helps "dry out" the clothes.

    2. It is said that in ancient times a rich man with a bag of gold coins froze to death stranded on the surface of a frozen lake. Because the ice was frictionless, he could not push himself to shore. What could he have done to save himself had he not been so miserly?

    3. A proton and an electron are held in place on the x axis. The proton is at x = -d, while the electron is at x = +d. They are released simultaneously, and the only force that affects their motions is the electrostatic force of attraction between them. Which particle reaches the origin first? Give your reasoning.

    4. A particle is oscillating in simple harmonic motion. The time required for the particle to travel through one complete cycle is equal to the period of the motion, no matter what the amplitude is. But how can this be, since larger amplitudes mean that the particle travels further? Explain in terms of energy.
  2. jcsd
  3. Jan 19, 2009 #2
    1. centrifugal force is outward force associated with rotation, how the outward force would effect the water molecules

    3. think about Newtons second law F=ma, which is can be arranged to a=F/m.
    does a proton or newtron have greater mass?

    4. i don't know what the oscillation equations are off hand but the idea is greater amplitude results in larger energy in the system which results in greater kinetic and potential energy.

    PS it helps if you put equations your using into the question so that it can be explained in terms of what you are doing at the time.
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