Rotational Equilibrium and Rotational Dynamics


by ataglance05
Tags: dynamics, equilibrium, rotational
ataglance05
ataglance05 is offline
#1
Mar1-07, 08:21 PM
P: 43
1. The problem statement, all variables and given/known data
Question Details:
A 10 kg engine is rotating at the rate of 20 rad/sec about a point on a wire 3 meters in length with a working tensile strength of 1.8*106 N. The engine is fired and produces an acceleration of 1 rad/sec2. What's the maximum possible ω (angular velocity) (in other words: 1) whats's the fastest ω which doesn't break the wire?) 2)How long should the engine be fired to reach the maximum possible ω? 3)How far will the engine travel in meters while it's accelerating to the maximum possible ω?

2. Relevant equations

3. The attempt at a solution
I believe it's right, however this is only #1. Need help on #2 and #3.


Thanks!
Phys.Org News Partner Science news on Phys.org
NASA's space station Robonaut finally getting legs
Free the seed: OSSI nurtures growing plants without patent barriers
Going nuts? Turkey looks to pistachios to heat new eco-city
andrevdh
andrevdh is offline
#2
Mar2-07, 09:04 AM
HW Helper
P: 1,446
2 can be solved with the equation

[tex]w_f = w_i + \alpha t[/tex]

since the angular acceleration is sustained as long as the engine is firing. The intial angular speed is 20 and the final is 245 rad/s. Once you solved for the time use it in the other equation that will give the angle in radians that it turned through during the burn. Using the radius you can then calculate the total distance covered during this time.


Register to reply

Related Discussions
Rotational Equilibrium and Rotational Dynamics problem Introductory Physics Homework 1
Rotational Equilibrium and Dynamics Introductory Physics Homework 31
Rotational Equilibrium and Dynamics - :) Introductory Physics Homework 2
Rotational Equilibrium and dynamics Introductory Physics Homework 7
Rotational Equilibrium and Dynamics Introductory Physics Homework 6