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Homework Help: Net force

  1. Sep 20, 2006 #1
    ugh I've got problems with newton again. >.<

    On vacation, your 1500 kg car pulls a 540 kg trailer away from a stop light with an acceleration of 2.00 m/s^2.
    What force does the trailer exert on the car?

    F=ma so: Force of car is 1.08 kN and Force of trailer is 3.0 kN. I thought it would be 1.08-3.0 but I was wrong. What do I need to do?
  2. jcsd
  3. Sep 20, 2006 #2
    You need to invoke newton's 3rd law: the law of equal and opposite action-reaction pairs.
  4. Sep 20, 2006 #3
    Got it. Thanks. 1.08 kN. I acually got it the first time, only typed it in wrong. omg this class is going to kill me. I'm sure to have another question with in the next 3 minutes....
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