Go Back   Physics Help Forum > High School and Pre-University Physics Help > Kinematics and Dynamics

Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum

Reply
 
LinkBack Thread Tools Display Modes
Old May 26th 2010, 05:03 AM   #1
Junior Member
 
Join Date: Apr 2008
Posts: 6
Rotation about Fixed Axis

Hi,
Here's my question:
A uniform rod AB of mass m is released from rest when it is at 60degrees from the surface of the earth. Assuming the friction force between end A (that's the end that touches the surface) and the surface is large enough to prevent sliding, determine (for the instant just after release)
a) Angular acceleration of the rod
b) The normal reaction and the friction force at A.



This seems like (and probably is) an easy sum, but I'm pretty sure I'm screwing up.

I got part a). It's 3g/4L. The answer matches with the one given.

However, I don't know what to do about part b). I think one equation will be mg - N giving me the net torque in the clockwise direction. But, I'm not sure if the sin and cos components have to be taken or what?
The other one should probably be friction balancing out the net force.

Any help is appreciated. Thank you.

Last edited by Ruler of Hell; May 26th 2010 at 05:15 AM. Reason: Typo.
Ruler of Hell is offline   Reply With Quote
Reply

  Physics Help Forum > High School and Pre-University Physics Help > Kinematics and Dynamics

Tags
axis, fixed, rotation



Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes


Similar Physics Forum Discussions
Thread Thread Starter Forum Replies Last Post
rotation about fixed axis ling233 Kinematics and Dynamics 5 Dec 18th 2015 03:05 PM
Perpendicular and Parallel Axis Aman987 Periodic and Circular Motion 1 Sep 24th 2013 07:34 AM
Is speed of light fixed? khonics89 Light and Optics 3 Sep 2nd 2010 09:23 AM
tension along the x-axis Polskers Kinematics and Dynamics 1 Sep 21st 2009 04:45 AM
Velocity of particle on x axis goldenroll Kinematics and Dynamics 2 Sep 8th 2009 10:57 PM


Facebook Twitter Google+ RSS Feed