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: One SImple prob and another about resonance

  1. Apr 27, 2005 #1
    Which are true:

    A) If the mass of the pendulum doubles, the period increases.
    B) If the ship accelerates upward, the period does not change.
    C) If the ship moves upward with a constant velocity, the period decreases.
    D) If the ship accelerates downward at 9.8 m/s2, the pendulum will no longer oscillate.
    E) If the length of the pendulum is doubled, the new period will be T0 multiplied by the square root of 2.

    I'm just checking my answer here, wouldnt it only be A and E?

    A 0.950 kg mass is suspended from a spring with a spring constant of 159 N/m. The spring is attached to a rod which oscillates vertically at a frequency f. For what value of the frequency f will the system resonate?

    I have no idea what to do here... i don't even remember my prof. talking about resonance...
  2. jcsd
  3. Apr 27, 2005 #2


    User Avatar
    Science Advisor
    Homework Helper

    You have not stated the conditions in the first question. It makes no sense without them.

    A simple example of resonance is when you push someone on a swing, you have to match your pushes with the natural motion of the swing to increase its amplitude. That is resonance. See if you can apply that idea to this problem.
  4. Apr 27, 2005 #3
    Sorry, here's the conditions:
    A simple pendulum suspended in a rocket ship has a period T0. Assume that the rocket ship is hovering near the earth in a uniform gravitational field.
  5. Apr 28, 2005 #4


    User Avatar
    Science Advisor
    Homework Helper

    What do you think the answers are, and why?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook