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Fun Car Physics Problem. I swear it's wicked fun!

  1. Aug 22, 2008 #1
    You are travelling in your 2000 kg car at 9.2 m/s and wish to accelerate to 17.5 m/s in 3.08 seconds, how much work, to the nearest joule, is required?

    Okay so i don't even know hwo t ostart this problem. I know I need to find the
    initial amount of work being done by the car and then subtract it from the end amount of work. Any help?
  2. jcsd
  3. Aug 22, 2008 #2
    Give the formula for work and the formula for energy and it should be obvious.
  4. Aug 22, 2008 #3
    Well the formula for work is obviously Force times Displacement and the formula for energy is 1/2 mass times the velocity squared. Do I just find the difference in thier enery?
  5. Aug 22, 2008 #4
    Yes, the 3.08 seconds is unnecessary because we are interested in work and not power. The simplest formula for work is, [tex] W = \Delta E [/tex], i.e. change in energy.
  6. Aug 22, 2008 #5
    Ah I finally got it! Thankyou all! The 3.08 seconds was just relevant to the next question which was find the power in watts and that is just work divided by time. Thanks again!
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