Recent content by onaboat

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    How Long Does It Take a Block to Move 30cm with a Frictionless Pulley System?

    I found the torque to be 2.5 N*m. Then using T=I\alpha I found the angular acceleration to be 20 rad/s^2. Then using s=\Theta*r I found the distance the pulley moved was 1.2 radians. I then used the circular motion for of the kinematic equation I used before and got .35s. Does this seem right?
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    How Long Does It Take a Block to Move 30cm with a Frictionless Pulley System?

    A 1.5 kg block is connected by a rope across a 50 cm-diameter, 2.0 kg, frictionless pulley. A constant 10 N tension is applied to the other end of the rope. Starting from rest, how long does it take the block to move 30cm? I summed up the force of the tension and the force of gravity of the...
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    Derive Group Velocity: vg=vp+k(dvp/dk) and vg=vp-λ(dvp/dλ) Explained

    Homework Statement Starting from: vg=vp+k(dvp/dk) show that the group velocity can also be expressed by vg=vp-λ(dvp/dλ). Homework Equations I'm told that vg=vp+k(dvp/dk) with vg=group velocity and vp=phase velocity. I also know that k=(2π)/λ and ω=2πf. The Attempt at a Solution I...
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