Recent content by datdo

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    Difficult: Linear vs. Angular acceleration

    cos^-^1\frac{2}{3} I guess it just seems too simple...even for a mechanics problem...
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    Difficult: Linear vs. Angular acceleration

    understood. \alpha=\frac{3gsin(\pi/2 -\theta)}{2L} end of the board: a_e=\frac{3gsin(\pi/2 -\theta)}{2} g\leq\frac{3gsin(\pi/2 -\theta)}{2} \frac{2g}{3g}\leq sin(\pi/2 -\theta) \frac{2}{3}\leq cos\theta this more likely... B still confuses me..
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    Difficult: Linear vs. Angular acceleration

    sorry about that. its sin because torque is F\times r = Frsin\theta the angular acceleration increases as the angle decreases A) \alpha=\frac{3gsin\theta}{2L} end of the board: a_e=\frac{3gsin\theta}{2} g\leq\frac{3gsin\theta}{2} \frac{2g}{3g}\leq sin\theta...
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    Difficult: Linear vs. Angular acceleration

    Homework Statement A board of mass m and length L is hinged to the ground. Attached to the board is a cup of negligible mass and is positioned Rc away from the hinge. Also on the edge of the board a ball rests. When the board is dropped from an angle of theta the ball is meant to be...
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    Block sliding up moving ramp

    but the normal force due to the ramp has a horizontal component which is not canceled by any other force. Also if there were no horizontal force the block would continue moving to the right. Newton's first law. Also in response to LowlyPion: Energy is a scalar so you can't take components of it.
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    Center of Mass of a Hollow 2D Triangle

    hmm... i didn't think of that... A:(.5A,0) B:(0,.5B) hypotenuse:(.5A,.5B) \overline{x}=\frac{A*.5A+B*0+\sqrt{A^2+B^2}*.5A}{A+B+\sqrt{A^2+B^2}}=\frac{.5A^2+\sqrt{A^2+B^2}*.5A}{A+B+\sqrt{A^2+B^2}}...
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    Center of Mass of a Hollow 2D Triangle

    Homework Statement What is the center of mass a hollow 2D right triangle having legs of length A and B. The sides of the triangle are also extremely thin. Assume uniform density. Homework Equations \overline{x}=∫xmdx/∫mdx The Attempt at a Solution...
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    Block sliding up moving ramp

    v0 is completely horizontal
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    Block sliding up moving ramp

    I guess I should explain a bit: First things I thought were energy is conserved but momentum is not due to a external net force but I can still work with momentum if I just figure out the impulse. E_i = E_f p_i =p_f +J The problem I'm having is I don't know how to solve for time. Nor do I...
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    Block sliding up moving ramp

    Difficult: Block sliding up moving ramp Homework Statement A block of mass m with initial velocity of v0 slides up up a ramp of angle \theta and mass M that is not pinned to the ground. It doesn't reach the top before sliding back down. What is the highest point that the block reaches in...
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