Recent content by SignaturePF

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    How Does Doubling the Mass Affect the Frequency of a Spring System?

    They will oscillate between getting relatively close to relatively far away
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    F=MA 2009 #23 (Power of a Spring)

    You need the two because you only have one sinxcosx not 2 as required by the double angle formula
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    F=MA 2009 #23 (Power of a Spring)

    So let's call Aw^2 k for simplicity P is -ksin(2wt)/2 P' is -k/4cos(2wt) We need to find where cos is -1 so P is positive and maximized. This occurs at 3pi\2 2wt = 3pi\2 w = 3pi\4t 1/T= 2pi\ T = 3\8t
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    How Does Doubling the Mass Affect the Frequency of a Spring System?

    Whoops. Where can I study oscillatory motion with two masses - my text is no help. Must it move x to the left?
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    F = MA 2009 # 14 (Momentum Quick Conceptual Question)

    I thought 1) no external forces 2) no external torque 3) energy loss due to heat/friction inside the block So the fact that there's an energy loss due to thermal energy negates everything?
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    How Does Angular Momentum Vary with Orbital Distance in Physics?

    Ya I see that but isn't it root(GM/a), where a is the semi major axis for object B. Doesn't that mean that the radius in the numerator won't cancel with the semi major axis on the denominator? That's where I was worried.
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    2009 F=MA Exam #6 (Conceptual Velocity Question)

    Oh ok, thanks, so I messed up the equation.
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    F=MA 2009 Exam # 18 (Pendulum, a small peg, and mass m)

    Ya I see why. It's because it takes T/4 to get to the mean. T/4 to get to the right extreme, and then the reverse to get back. So it makes sense that its T/4. What's next?
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    F=MA 2009 #23 (Power of a Spring)

    F = ma = md^2x/dt^2 F = mdv/dt Power = d^2x/dt^2 * dx/dt Power = d^3x/dt^3 Power = -Aw^3cos(wt)? Actually I think I violated rules of multiplication.
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    How Does Doubling the Mass Affect the Frequency of a Spring System?

    Well if A is the amplitude, I would think that as one block is X to the right, the other would be A-X to the left. The spring is stretched by A-X + X = A? The force that the spring exerts on the right-hand block I'm not sure how to write.
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    2009 F=MA # 24 (A block tipping down an incline)

    tanθ = b/a Ahh, now I can solve the problem. I found before that Ff > mgsinθ umgcosθ > mgsinθ u > tanθ u > b/a This is correct. Thanks so much. Not only were you EXTREMELY helpful, but you helped me in a very timely fashion. Your help is greatly appreciated. Ok so the main concepts in the...
  12. S

    2009 F=MA # 24 (A block tipping down an incline)

    Here's my diagram: Is this what you're saying?
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