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Homework Help: Motion Eqaution and Newtons Law Problem?

  1. Oct 2, 2009 #1
    A projectile has been launched and moves according to the equations: y = 6.00 + 3.45t − 7.20t2 m, and x = 17.0t m. (a) Do these equations describe an object launched on Earth? (b) Assume the object is a slide rule of mass 0.207 kg. What force is being exerted on it?

    I know part a is no, since the acceleration isnt 9.8, but I have no idea how to do part b? any help?
  2. jcsd
  3. Oct 2, 2009 #2

    Do you understand what each of the terms in your equation of motion mean? Remember that [tex]s=s_{i}+v_{i}t+\frac{1}{2}at^{2}[/tex]

    Last edited: Oct 2, 2009
  4. Oct 2, 2009 #3


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    Homework Helper

    So if y is displacement, how does one find velocity and hence acceleration?

    Now use the message below.

  5. Oct 2, 2009 #4
    ok, I see just take the 2nd derivative of y and x and multiply by mass

    thanks guys
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