Recent content by Paquete

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    Supposed to be an easy question about WORK

    mms05 is right, the displacement on a curved ramp would be different than that on a straight ramp, but, in this particular problem you can use a different approach , just like Teegvin said, in order to calculate work. W = - (Uf - Ui) where Uf is the final potential energy and Ui is...
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    Solve Dynamics Problem for Particle on Semicilinder

    Ok, i see what you mean. But is there any way to do the problem with this ecuation? m(-\rho \dot{\theta^2} \hat{\rho} + \rho \ddot{\theta} \hat{\theta}) = N \hat{\rho} + T \hat{\theta} - mg\sin(\theta)\hat{\rho} - mg\cos(\theta)\hat{\theta} i mean, imposing the conditions in it...
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    Calculating Work Done in Lifting a Weight with a Spring

    work is the difference between the final and initial potential energy of the system (although this only applies if the force is conservative), that's why you were getting a negative sign.
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    Solve Dynamics Problem for Particle on Semicilinder

    Sorry, i made a mistake a_0 = R\ddot{\theta} \Longleftrightarrow a_0 = R\frac{d\dot{\theta}}{d\theta} \frac{d\theta}{dt} \Longleftrightarrow a_0d\theta = R\dot{\theta}d\dot{\theta} if we now integrate the left side between \theta = 0 and \theta = \theta_1 and the right side between...
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    Solve Dynamics Problem for Particle on Semicilinder

    Sorry, i had a final exam yesterday, so i checked your answer but i planned on responding today. i have a different approach a_0 = R\ddot{\theta} \Longleftrightarrow a_0 = R\frac{d\dot{\theta}}{d\theta} \frac{d\theta}{dt} \Longleftrightarrow a_0d\theta = R\dot{\theta}d\dot{\theta}...
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    Solve Dynamics Problem for Particle on Semicilinder

    I'm sorry, you're absolutely right. I wasn't thinking on the meaning of the ecuations, just trying to solve them and overlooked the fact that \rho \dot{\theta^2} is \frac{v_t}{r}. v_t being tangential velocity. So, the ecuation for \hat{\rho} would be: m(-\rho \dot{\theta^2}) = N...
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    Solve Dynamics Problem for Particle on Semicilinder

    Are you sure? because a0 will generate an acceleration in \hat{\theta} and the radial component of the wight generates the acceleration in \hat{\rho} i know the condition for the first question is that the normal (N) becomes 0and for the second one that the tension becomes 0, but in both...
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    Solve Dynamics Problem for Particle on Semicilinder

    sorry, here goes an image of the system http://img220.imageshack.us/my.php?image=dibujo2lr.jpg jajajaja, it doesn't look too good, but you'll get the picture
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    Solve Dynamics Problem for Particle on Semicilinder

    Hi, I'm from Chile, so i had to translate the problem from spanish and my english ain't that good so if you don't understand something, please tell me. A particle of mass m is initially at rest at the edge of a horizontal semicilinder of radius R (theta (t=0)=0). The particle is tied to an...
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