1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Issues with motion and force

  1. Sep 20, 2004 #1
    My problem invloves a car with a mass of 1520kg. It's traveling with a speed of 15.0 m/s. I'm asked to find the magnitude of the horizontal net force that is require to bring the car to a halt at 57.5m.

    My reasoning begins, in that I think I should be finding the acceleration and once I've found the acceleration I can find the total force. But, this is producing a rather large number for me that is negative.

    To find the acceleration I used the equation: a = V^2 - Vo^2 / 2x

    Using that equation my answer was -1.96

    I then plugged that into the equation for net force which was: net force = m(a)

    Plugging in the variables I know in that got me the answer -2973.9 But I can't imagine that this is correct.

    Any help would be appreciated.
  2. jcsd
  3. Sep 20, 2004 #2
    Again, nevermind. What I did was correct however, I should have been leaving out the negative sign. Sorry about this.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook