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: Is this a conservation of energy problem?

  1. Dec 4, 2017 #1
    1. The problem statement, all variables and given/known data

    I'm sorry but I don't have the exactly problem written down but I know the givens.

    So the question involves finding work done on a pendulum hanging from the ceiling.

    2. Relevant equations
    I was given the the length of the string is 1m. That a mass hangs at the bottom of string and it's 2kg. That it displaces .5 meters to the left.

    3. The attempt at a solution
    I was thinking that I had to do mgh = 1/2mv^2 but then did know how to get velocity.

    Any clues?
     
  2. jcsd
  3. Dec 5, 2017 #2

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    Velocity of what?

    Did you draw a sketch? What is the height of the mass at the end (and initially)?
     
  4. Dec 5, 2017 #3
    Yes I've done the sketch. There was no given height!! That's why I'm kinda a bit lost and confused.
     
  5. Dec 5, 2017 #4
    Velocity
    But you have given mass displaced.5 meter and lenght of string 1meter from this you can calculate height
     
  6. Dec 5, 2017 #5
    I'm not really recognizing how we can find height?
     
  7. Dec 5, 2017 #6
    I don't think you have done the sketch properly. Draw the sketch and dimension where the mass is located.
     
  8. Dec 5, 2017 #7
     

    Attached Files:

  9. Dec 5, 2017 #8
    You show the figure i have posted?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted