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Homework Help: I need some help with some basic material

  1. Oct 1, 2004 #1
    I can't seem to figure these problems if anyone can give me the concept and start me off that would be great.

    Thanks in advance

    Problem one: A car is traveling at a constant speed of 27 m/s on a highway. At the instant this car passes an entrance ramp, a second car enters the highway from the ramp. The second car starts from rest and has a constant acceleration. What acceleration must it maintain so that the two cars meet for the first time at the next exit which is 1.8 km away?

    Problem two: A bus stop to pick up riders. A woman is running at a constant velocity of +5.0 m/s in an attempt to catch the bus When she is 11 m from the bus, it pulls away with a constant acceleration of +1.0 m/s^2. From this point, how much time does it take her to reach the bus if she keeps running with the same velocity?

    *edit*
    Oh sorry i posted this after i read the before you post thread Once again Im sorry for posting Homework help here
     
    Last edited: Oct 1, 2004
  2. jcsd
  3. Oct 1, 2004 #2

    Pyrrhus

    User Avatar
    Homework Helper

    For the first problem consider the formulas

    [tex] vt = x [/tex]

    [tex] \frac{1}{2}at^2 = x [/tex]

    You go the speed for the car and the distance x they will both travel, what can you do with that?

    For the second problem

    She will do

    [tex] vt = x + 11 [/tex]

    while the bus will do

    [tex] \frac{1}{2}at^2 = x [/tex]
     
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