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 some help to answer Some questions

  1. Feb 14, 2006 #1
    Hi Guys,

    I face some problems answering below questions. Anyone can help to answer?

    Q1: One end of a string of length 1.0m is tied to body of mass 0.5kg. It is whirled in a vertical circle. If its angular speed is 3rev/s, calculate the tension in the string at the highest and lowest points.

    Q2: (a) Calculate the angular speed of the earth.
    (b) Calculate the
    (i) Energy
    (ii) Torque and (iii) average power
    required to accelerate the Earth in 1 day from rest to its present angular speed.
    (Mass of the Earth : 6x10 power 24 kg , radius of erath = 6400km)


  2. jcsd
  3. Feb 14, 2006 #2
    We cannot just give you the answers, that's against the PF Guidelines. Please show us what you have done so far.


    ps : as a hint to Q1. Can you link the orbital velocity to an acceleration (centripetal) ? There is a nice and easy formula for this. If you do this, you are on your way...
    Last edited: Feb 14, 2006
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook