Physics homework help...

Discussion in 'General Off-Topic Chat' started by Westside, Oct 13, 2008.

  1. Westside
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    Westside Sogdiana

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    A car speeds at 15m/s past a police car at rest. After 5s, the police car starts to chase the speeder accelerating uniformly at 0.5m/s^2. At what position from the starting point does the police catch the speeder?

    I am having a VERY hard time with this question... [​IMG]
     
  2. FAST6191

    FAST6191 Techromancer

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    Car has a 5 second headstart at 15m/s or 75m.

    Police accelerate at 0.5ms^-2

    s = ut +1/2at^2

    Car distance = 75 + 15t
    Police distance = s = ut +1/2at^2 = 0 + 1/2 * 1/2 * t^2


    Car distance = police distance
    75 + 15t = 1/2 * 1/2 * t^2

    I assume you can solve a quadratic equation.
     
  3. Westside
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    Westside Sogdiana

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    Thank you, that clears it up a whole lot! [​IMG]
     
  4. Little

    Little I r Little

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    Good works guys =)