Uniform circular motion Definition and 312 Threads

In physics, circular motion is a movement of an object along the circumference of a circle or rotation along a circular path. It can be uniform, with constant angular rate of rotation and constant speed, or non-uniform with a changing rate of rotation. The rotation around a fixed axis of a three-dimensional body involves circular motion of its parts. The equations of motion describe the movement of the center of mass of a body. In circular motion, the distance between the body and a fixed point on the surface remains the same.
Examples of circular motion include: an artificial satellite orbiting the Earth at a constant height, a ceiling fan's blades rotating around a hub, a stone which is tied to a rope and is being swung in circles, a car turning through a curve in a race track, an electron moving perpendicular to a uniform magnetic field, and a gear turning inside a mechanism.
Since the object's velocity vector is constantly changing direction, the moving object is undergoing acceleration by a centripetal force in the direction of the center of rotation. Without this acceleration, the object would move in a straight line, according to Newton's laws of motion.

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  1. L

    How Long Does a Spin Take at 33 1/3 RPM?

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  2. G

    Ball Suspended from Ceiling (Uniform Circular Motion)

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  3. G

    Airplane Pilot, dealing with Uniform Circular Motion

    Homework Statement A 78.4-kg airplane pilot pulls out of a dive by following, at a constant speed of 162 km/h, the arc of a circle whose radius is 321.0 m. At the bottom of the circle, he is accelerating at 6.31 m/s upwards. What is the force exerted on the pilot by the airplane seat...
  4. K

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    Homework Statement A satellite has a mass of 5700 kg and is in a circular orbit 4.2 multiplied by 10^5 m above the surface of a planet. The period of the orbit is two hours. The radius of the planet is 4.25 multiplied by 10^6 m. What is the true weight of the satellite when it is at rest on...
  5. G

    Uniform Circular Motion Problem

    Homework Statement A circular curve of highway is designed for traffic moving at 93 km/h. Assume the traffic consists of cars without negative lift. (a) If the radius of the curve is 210 m, what is the correct angle of banking of the road? (b) If the curve were not banked, what would be the...
  6. P

    Uniform Circular Motion Hills and Cars

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  7. G

    Uniform circular Motion Problem

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  8. M

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  9. W

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  10. J

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  11. C

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  13. T

    Uniform circular motion - frequency vs. centripetal force.

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  14. D

    Identifying the forces acting on masses in uniform circular motion.

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  15. U

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  16. O

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  17. P

    Uniform Circular motion, angular velocity and Friction

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  18. A

    Uniform Circular Motion: Bead on a String Problem Solution

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  19. L

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  20. N

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  21. H

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  22. C

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  23. P

    Understanding Velocity and Acceleration in Uniform Circular Motion

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  24. S

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  25. P

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  26. G

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  27. T

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  28. C

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  31. S

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  32. C

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  33. S

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  34. A

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  35. S

    Understanding Uniform Circular Motion: Explained and Tested | Stephen

    I had a test today, there was a question about uniform circular motion. Isn't the velocity constant since the speed is constant? I know angular velocity is constant, but the question's answers only state constant speed or velocity. Thank you. Stephen
  36. E

    Deriving a Uniform Circular Motion Equation

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  37. J

    Uniform Circular Motion, Rotational Motion, Torque, and Inertia

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  38. J

    Uniform Circular Motion in Lagrangian Formalism

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  39. Y

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  40. F

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  41. J

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  42. clope023

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  43. I

    Uniform circular motion of satellite

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  44. B

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  45. S

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  46. S

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    Homework Statement A 100 g bead is free to slide along an 80 cm long piece of string ABC. The ends of the string are attached to a vertical pole at A and C, which are 40 cm apart. When the pole is rotated about its axis, AB becomes horizontal I know this question has been posted before...
  47. B

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  48. D

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  49. K

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  50. S

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