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Homework Help: Physics questions

  1. Jan 7, 2008 #1
    1. The problem statement, all variables and given/known data

    Can someone help me with these problems?

    1) The drum of a washing machine reduces the rpms from 900 rpm to 300 rpm. In doing so, it performs 50 rotations. Calculate:

    a) angular accelartion b) the time required to perform 50 rotations.

    2)A railway engine starts from rest on the peak of a declined surface with an angle of inclination 1%. It covers 1.200m downwards due to the gravitational force and continues thereafter on an even track. The tractive resistance is constant and rated at 500N per ton. Calculate:

    a) the velocity v at the base of the inclined track.
    b) The distance covered by the train on the level track until it stops.

    3) A bullet of mass m=1 kg moves at a speed of 12m/s and collides in the center of another bullet with a mass of 2kg that moves at a speed of 24m/s in opposite direction.

    a) the velocity of each bullet after the impact, if the coefficeint of impact 2/3

    b) the velocity of each bullet, if these behave as one body with the coefficient of impact 2/3

    c) the velocity of each bullet, if the impact is completely inelastic with the coefficient of at impact 2/3.

    2. Relevant equations

    What equations can be used to answer these problems?

    3. The attempt at a solution

    I find some parts to the answer but can not completely finish the problem off, can someone help?
  2. jcsd
  3. Jan 7, 2008 #2


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    Homework Helper

    Show what parts you've done, and explain what is giving you trouble with the rest of the questions. Look up the relevant equations in your textbook. Where did you find the equations you used for the parts you could get?
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