What is Velocity vector: Definition and 99 Discussions

The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north). Velocity is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of bodies.
Velocity is a physical vector quantity; both magnitude and direction are needed to define it. The scalar absolute value (magnitude) of velocity is called speed, being a coherent derived unit whose quantity is measured in the SI (metric system) as metres per second (m/s or m⋅s−1). For example, "5 metres per second" is a scalar, whereas "5 metres per second east" is a vector. If there is a change in speed, direction or both, then the object has a changing velocity and is said to be undergoing an acceleration.

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  1. L

    Elliptical motion in polar coordinates

    I think I have completed the exercise but since I have seldom used polar coordinates I would be grateful if someone would check out my work and tell me if I have done everything correctly. Thanks. My solution follows. Since ##\left(\frac{x}{a}\right)^2+\left(\frac{y}{b}\right)^2=1## it follows...
  2. L

    Solving a Celestial Mechanics Task with Velocity Vector Scattering

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  3. hjam24

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  4. Gamma Anon

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  5. V

    Direction of of the velocity vector for particles in a sound wave

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  6. E

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  7. WMDhamnekar

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  8. winnie_d_poop

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  9. justinpaul

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  10. E

    Finding time from a velocity vector

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  11. P

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  12. G

    Mechanics: Angular Velocity Vector Questions

    Answers are the following : (i) v=(2cost)i - (2sint)j -(1/2)k (ii)2.06m/s (iii)2m/s^2 horizontally towards the vertical axis, making an angle of pi/4 with both the I and j axes.
  13. dkhurana

    I Four Velocity Vector: why divide by time according to the particle?

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  14. E

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  15. W

    B Measurement of an unknown velocity vector of a closed space

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  16. V

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  17. Adesh

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  18. R

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  19. ashhlyn

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  20. G

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  21. T

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  22. Poetria

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  23. L

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  24. S

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  25. Pushoam

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  26. S

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  27. R

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  28. Arman777

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  29. doktorwho

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  30. C

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  31. M

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  32. D

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  33. H

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  34. J

    What are the x- and y-components of the velocity vector?

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  35. NiendorfPhysics

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  36. V

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  37. Poetria

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  38. Toon

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  39. D

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  40. P

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  41. C

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  42. T

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  43. A

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  44. M

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  45. U

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  46. B

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  47. V

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  48. R

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  49. G

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  50. A

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