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: Help with Newton's 2nd Law

  1. May 8, 2007 #1
    Hi, I'm having trouble with a problem dealing with Newton's Second Law, and was wondering if anyone could give me a hint as to how I should solve it (general equation, process, whatever)? I'm not asking for somebody to solve it, I just need some help...:smile:

    1. The problem statement, all variables and given/known data
    A student, standing on a scale in an elevator at rest, sees that his weight is 840 N. As the elevator rises, his weight increases to 1050 N, then returns to normal. When the elevator slows to a stop at the 10th floor, his weight drops to 588 N, then returns to normal. Determine the acceleration at the beginning and end of the trip.

    2. Relevant equations

    acceleration= net force/mass and maybe Fg= ge * mass

    3. The attempt at a solution
  2. jcsd
  3. May 8, 2007 #2
    This is a two part problem: treat the beginning and end of the trip as two separate problems. For each situation, draw a free-body diagram of the forces acting on ElevatorMan, then algebraically add up the forces associated with each arrow.
    Welcome aboard, and hope that helps!
  4. May 8, 2007 #3
    Alright, thanks so much!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook