What is Rotational motion: Definition and 610 Discussions

A rotation is a circular movement of an object around a center (or point) of rotation. The geometric plane along which the rotation occurs is called the rotation plane, and the imaginary line extending from the center and perpendicular to the rotation plane is called the rotation axis ( AK-seez). A three-dimensional object can always be rotated about an infinite number of rotation axes.
If the rotation axis passes internally through the body's own center of mass, then the body is said to be autorotating or spinning, and the surface intersection of the axis can be called a pole. A rotation around a completely external axis, e.g. the planet Earth around the Sun, is called revolving or orbiting, typically when it is produced by gravity, and the ends of the rotation axis can be called the orbital poles.

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  1. R

    Center of mass on plank problem

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  2. Janet1234

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  3. floraha

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  4. hpthgpjo

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  5. Arman777

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  6. Arman777

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  7. mamadou

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  8. L

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  9. welssen

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  10. R

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  11. Avijit

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  12. lightofthemoon

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  13. anon11

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  14. R

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  15. Likith D

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  16. K

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  17. patrickmoloney

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  18. W

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  19. S

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  20. A

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  21. ChrisBrandsborg

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  22. Q

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  23. O

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  24. H

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  25. H

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  27. X

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  28. X

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  29. X

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  30. D

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  31. D

    Understanding Velocity and Acceleration in Rotational Motion

    RHomework Statement A What is the velocity of the mass at a time t? You can work this out geometrically with the help of the hints, or by differentiating the expression for r⃗ (t) given in the introduction. (Figure 2) Express this velocity in terms of R, ω, t, and the unit vectors i^ and...
  32. LiliPling

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  33. B

    Best way of turning rotational motion into linear motion?

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  34. RoboNerd

    What Is the Correct Formula for Calculating Power in Rotational Motion?

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  35. RoboNerd

    Ratio of angular speed with conservation of energy

    Homework Statement A ball rolls down an incline plane without slipping. What is the ratio of its angular velocity at h/3 to its angular velocity at 2h/3? 1) 1:2 2) 1:sqrt(2) 3) 1:1 4) sqrt(2):1 5) 2:1 Homework Equations Conservation of energy with provisions for rotational and...
  36. B

    Converting Rotational Motion to Pendulum-Like Oscillation

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  37. xXhumans0monstersXx

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  38. J

    Ball rolling down a ramp, no slipping, + friction (conceptual question)

    So if a ball is rolling down a ramp and not slipping, you have two torques... the mg*sin(theta) portion of gravity and the (mu)mgcos(theta) for friction. My question is this: Does this friction force remove energy from the ball? (I know it affects the balls rotation but this is just changing...
  39. J

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  40. P

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  41. RoboNerd

    Question on ap physics c 2012 free response

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  42. hzx

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  43. RoboNerd

    Question on AP Physics C FRQ 2013. #3

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  44. RoboNerd

    Question on Rotational Motion and Torque Theory

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  45. manuel60

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  46. RoboNerd

    Why Does the Solution Use (T2 - T1) * R for Net Torque?

    Homework Statement https://web.njit.edu/~gary/111/assets/HW10_SOL.pdf'][/PLAIN] https://web.njit.edu/~gary/111/assets/HW10_SOL.pdf The problem is on page 3 of the document along with relevant solutions. Homework Equations F=ma, and Sigma Torques = (moment of inertia) * angular acceleration...
  47. S

    Dumbell collision, COM and rotational motion

    Say you've got a dumbbell-type object sitting still in space, and a mass comes in from below and strikes it. We've got a collision. If the mass strikes the dumbbell away from the center of mass, then it will cause the dumbbell to do two things (1) rotate, (2) the center of mass will move up...
  48. P

    Rotational Motion: Momentum Conservation

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  49. REVIANNA

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  50. M

    Rotational Motion Homework: K1+U1=K2+U2

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