Recent content by blue5t1053

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    Finding Final Velocity of a Falling Rotating Rod

    Would this be right? m*g*h = \frac{1}{2} * m * v^{2} 9.8 \frac{m}{sec^{2}} * 1 m = \frac{1}{2} * v^{2} \sqrt{\frac{9.8 \frac{m}{sec^{2}} * 1 m}{\frac{1}{2}}} = v v = 4.427 \frac{m}{sec} \ ; \ then *2 m \ for \ top \ of \ rod v = 8.85 \frac{m}{sec}
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    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    So if I revisit method one... L_{child} = (3.91 m) * (199 kg) * (3.09 \frac{m}{sec}) = 2404.3 \frac{kg*m^{2}}{sec} L_{merry-go-round} = (3.91 m) * (371.531 kg) * (0 \frac{m}{sec}) = 0 \frac{kg*m^{2}}{sec} I_{child} = (199 kg) * (3.91 m)^{2} = 3042.33 kg*m^{2} method \ 1 \ \Rightarrow...
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    Finding Final Velocity of a Falling Rotating Rod

    I am to assume that the ground is frictionless and that it will rotate from where the rod had made contact with the ground. I can't find any way to calculate it without mass. What principle would I use to find it? I tried using angular velocity, but I couldn't make it work.
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    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    I had a lapse of thought there. So I shouldn't include the mass of the merry-go-round?
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    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    I thought 'p' was for momentum of the merry-go-round. The only object moving initially is the child. If I apply the child attached to the merry-go-round initially with the starting speed, if I understand this correctly, would be L = (3.91 m) * (199 kg) * (3.09 \frac{m}{sec}) = 2404.3...
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    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    L = r *p L = (3.91 m) * (371.53 kg) = 1452 kg*m \ ; \ merry-go-round \ without \ child
  7. B

    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    Am I to assume that 'm' is total mass of the system (merry-go-round + child) or merry-go-round for interia of the merry-go-round?
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    Why Does the Merry-Go-Round Spin at 0.276 rad/sec After the Child Jumps On?

    Problem: In a plyground there is a small merry-go-round of radius 3.91 m and rotational inertia 5.68e+03 kg m^2. A child of mass 199 kg runs at a speed of 3.09 m/sec tangent to the rim of the merry-go-round when it is at rest and then jumps on. Assume no friction in the bearing of the...
  9. B

    Finding Final Velocity of a Falling Rotating Rod

    Problem: A rigid assembly is made of a light weight rod 2 m long and a heavy gold ball which is attached at the middle of the rod. The rigid assembly initially rests with one end on the ground in a vertical position. If released what speed does the top of the rod have when it strikes the...
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    How Do You Calculate Initial Angular Velocity with Constant Acceleration?

    Question: A flywheel has a constant angular acceleration of 2 rad/sec^2. During the 19 sec time period from t1 to t2 the wheel rotates through an angle of 15 radians. What was the magnitude of the angular velocity of the wheel at time t1? Hint: let t1=0 sec, and t2=t Equations: \vartheta...
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    Linear Acceleration of a turntable

    2 \times \pi \times \frac{.55 rev}{sec} = 3.45575 \frac{rad}{sec} 3.45575 \frac{rad}{sec} \times .18 m = .622035 \frac{m}{sec} \frac{(.622035 \frac{m}{sec})^{2}}{.18 m} = 2.1496 \frac{m}{sec^{2}} Thank you!
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    Linear Acceleration of a turntable

    Oh my, I forgot about radius, haha. I was too concerned with the conversion to meters from centimeters!
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    Linear Acceleration of a turntable

    2 \times \pi \times \frac{.55 rev}{sec} = 3.45575 \frac{rad}{sec} \frac{3.45575 \frac{rad}{sec}}{.36 m} = 9.59931\frac{m}{sec} (9.59931 \frac{m}{sec})^{2} \times .36 m = 33.1728 \frac{m}{sec^{2}} Is this correct?
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    Linear Acceleration of a turntable

    Problem: What is the linear acceleration of a point on the rim of a 36 cm diameter turntable which is turning at 33 rev/min? My Work: T = \frac{2 \pi r}{v}; v = \frac{2 \pi r}{T} a_{r} = \frac{v^{2}}{r} \frac{33 rev}{min} \times \frac{1 min}{60 sec} = \frac{.55 rev}{sec} \frac{2...
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    Rotation of a disk - find angular acceleration

    Problem: A disk rotates about its central axis starting from rest and accelerates with constant angular acceleration. At one time it is rotating at 12 rev/s; 69 revolutions later, its angular speed is 33 rev/s. Calculate (a) the angular acceleration, (b) the time required to complete the 69...
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