Results 1 to 4 of 4

Math Help - Angular Momentum

  1. #1
    Newbie
    Joined
    Oct 2008
    Posts
    6

    Angular Momentum

    A particle rotates in a circular orbit about a point located 30cm away, with angular speed 2 rad s^-1. If the angular momentum is 0.2 Js, determine the mass of the particle.

    I used L=mr^2 omega and got 1.11kg

    A constant torque of 0.2Nm accelerates the particle for 5s. Determine the final angular momentum of the particle. I'm not sure how to do this or which equation to use.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,110
    Thanks
    976
    Quote Originally Posted by PurplePenguin View Post
    A particle rotates in a circular orbit about a point located 30cm away, with angular speed 2 rad s^-1. If the angular momentum is 0.2 Js, determine the mass of the particle.

    I used L=mr^2 omega and got 1.11kg
    ok

    A constant torque of 0.2Nm accelerates the particle for 5s. Determine the final angular momentum of the particle. I'm not sure how to do this or which equation to use.
    \alpha = \frac{\tau}{I}

    L = I\omega_f = I(\omega_o + \alpha t)
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Oct 2008
    Posts
    6
    Will the moment of inertia still be the same for the second part? Should I calculate it using mr^2?

    If I do I get:
    I = 0.1
    = 0.2/0.1 = 2
    L = 0.1(2 + (2 x 5)) = 1.2

    Is this correct?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,110
    Thanks
    976
    Quote Originally Posted by PurplePenguin View Post
    Will the moment of inertia still be the same for the second part? Should I calculate it using mr^2?

    If I do I get:
    I = 0.1
    = 0.2/0.1 = 2
    L = 0.1(2 + (2 x 5)) = 1.2

    Is this correct?
    moment of inertia will not change.

    calculations are correct ... where are your units?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] angular momentum - kepler's law
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: September 26th 2011, 07:39 PM
  2. [SOLVED] Quantum Mechanics - Angular Momentum part 3
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: February 24th 2011, 12:13 PM
  3. [SOLVED] Quantum Mechanics - Angular Momentum part 2
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: February 23rd 2011, 02:27 PM
  4. [SOLVED] Quantum Mechanics - Angular Momentum
    Posted in the Advanced Applied Math Forum
    Replies: 4
    Last Post: February 23rd 2011, 02:19 PM
  5. Commutation relation - angular momentum operator
    Posted in the Advanced Applied Math Forum
    Replies: 3
    Last Post: April 27th 2009, 12:57 AM

Search Tags


/mathhelpforum @mathhelpforum