Register to reply

Angular acceleration problem

by seboastien
Tags: acceleration, angular
Share this thread:
seboastien
#1
Aug18-11, 05:24 AM
P: 53
1. The problem statement, all variables and given/known data

angular acceleration of line a= -2w^2 rad/s

when theta=pi/6, w= 10 rad/s

what is angular velocity when theta= pi/3?

2. Relevant equations

chain rule

3. The attempt at a solution

w= e^-2theta is my answer, but I know this is wrong

I know that this question is really easy, but I just don't know how to get it
Phys.Org News Partner Science news on Phys.org
Experts defend operational earthquake forecasting, counter critiques
EU urged to convert TV frequencies to mobile broadband
Sierra Nevada freshwater runoff could drop 26 percent by 2100
rock.freak667
#2
Aug18-11, 05:38 AM
HW Helper
P: 6,202
Well you should know that α= -2ω2 means that dω/dt = -2ω2

which is an easily solvable DE once you 'separate the variables' i.e. put all the things with ω on one side and t on the other then integrate both sides.
seboastien
#3
Aug18-11, 05:42 AM
P: 53
But then I end up with t=1/2w, how do I find the rest of the answer?

seboastien
#4
Aug18-11, 06:06 AM
P: 53
Angular acceleration problem

Someone please help me!!!!
rock.freak667
#5
Aug18-11, 08:32 AM
HW Helper
P: 6,202
Quote Quote by seboastien View Post
But then I end up with t=1/2w, how do I find the rest of the answer?
I now saw that you have ω and θ so forget my above post and replace α with ω*dω/dθ and integrate again. Do not forget the constant of integration which you can find with the conditions they gave you.
seboastien
#6
Aug18-11, 09:55 AM
P: 53
Yes, that was my problem all along... I forgot to add the constant!! Thanks.


Register to reply

Related Discussions
Did I do this angular acceleration problem right? Introductory Physics Homework 4
Angular Acceleration Problem.. Why am I not right? Introductory Physics Homework 7
Angular Acceleration problem... Introductory Physics Homework 2
Angular acceleration problem Introductory Physics Homework 9