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: Need help with this

  1. Oct 9, 2004 #1
    A weight of mass 2.00 kg hangs on a lineair spring with spring constant k= 3.25N/m^2. The weight is held at height y=0 so that the spring is not extended and exerts no force on the weight. When the weight falls, there is a damping force is proportional to the velocity. The initial velocity of the weight is zero. At time t=0, the weight is released. It falls and executes damped oscillations. Eventually, it comes to rest. For this situation, Newtons second law can be written as : m*(d^2*y/d*t^2)=-(dy/dt)-(k*y)-m*g
    Here -(dy/dt) is the damping force, -ky is the force exerted by the spring and -mg is the force of gravity

    Question: let y_final be the height of the weight after it stops moving..what is y_final?

    I dont know how to solve this....pls who can give me hints?
  2. jcsd
  3. Oct 9, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Sounds like a trick question. Hint: When the mass comes to rest, it will be in equilibrium.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook