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New to physics this year, please help!

  1. Sep 10, 2006 #1
    I'm new to physics, and would like a little help in solving this problem.

    I am in a problem with Newton's second law...the formula is Force = Mass times Acceleration.

    The problem states: A truck produces a force of 100 N as it accelerates from 5 m s to 10 m s in 5 seconds. What is the Mass of the truck, and what is the weight of the truck?

    I can't seem to understand how to find the acceleration and the weight.

    Can someone help me?

  2. jcsd
  3. Sep 10, 2006 #2
    Ok, so you obviously know that you'll be needing [tex]f=m a[/tex] for this one. You want the mass, it gives you the force directly, the only thing that YOU need to figure out is the acceleration.

    Remember that acceleration is given by the equation [tex]a=\frac{v}{t}[/tex]

    You are given the change in velocity in the question (from 5m/s to 10m/s) and you also know the time it takes. Simply plug all those values into the equation and you should be able to solve for Mass.

    After that, you should know by now that 'weight' is given by [tex]F=m g[/tex] where g is the acceleration due to gravity [tex]9.81 \frac {m}{s^2}[/tex] Just solve for F!
  4. Sep 10, 2006 #3
    thanks for gettn back so quickly
    so would the equation to find the acceleration be

    10m/s-5/ms divided by 5 sec
  5. Sep 11, 2006 #4
    yup, that's exactly right! So it would end up just being [tex]1 \frac{m}{s^2}[/tex]

    from there you shouldn't have had any more problems
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