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Homework Help: Basic Physics Homework

  1. Sep 13, 2008 #1
    *** Basic Physics Homework ***

    PLEEZ HELP!!!!! these are due at 8. i got transfered to this new school and they are much farther ahead of us in the curriclulum please HELP ME :(


    #4 PART 1

    Two cars travel in the same direction along a
    straight highway, one at a constant speed of
    55 mi/h and the other at 66 mi/h.
    Assuming they start at the same point, how
    much sooner does the faster car arrive at a
    destination 10 mi away? Answer in units of
    Answer =1.81 min

    #4 PART 2

    How far must the faster car travel before it
    has a 13 min lead on the slower car? Answer
    in units of mi.


    A tennis ball with a speed of 8 m/s is thrown
    perpendicularly at a wall. After striking the
    wall, the ball rebounds in the opposite direc-
    tion with a speed of 7 m/s.
    If the ball is in contact with the wall for
    0.012 s, what is the average acceleration of
    the ball while it is in contact with the wall?
    Answer in units of m/s2.


    A subway train starting from rest leaves a
    station with a constant acceleration. At the
    end of 9.27 s, it is moving at 22.6188 m/s.
    What is the train’s displacement in the first
    6.29433 s of motion? Answer in units of m.


    Highway safety engineers build soft barriers
    so that cars hitting them will slow down at a
    safe rate. A person wearing a safety belt can
    withstand an acceleration of 300 m/s2.
    How thick should barriers be to safely stop
    a car that hits the barriers at 89.4 km/h?
    Answer in units of m.


    Two particles are at the same point at the
    same time, moving in the same direction. Par-
    ticle A has an initial velocity of 7.9 m/s and
    an acceleration of 2.8 m/s2. Particle B has an
    initial velocity of 2.9 m/s and an acceleration
    of 5.2 m/s2.
    At what time will B pass A? Answer in

    units of s.
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Sep 13, 2008 #2


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    Homework Helper

    Re: *** Basic Physics Homework ***

    We are not going to do your homework for you. Show what you've attempted, even if you think it's wrong. Then we can help.
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