What is Kinetic energy: Definition and 1000 Discussions

In physics, the kinetic energy of an object is the energy that it possesses due to its motion.
It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest.
In classical mechanics, the kinetic energy of a non-rotating object of mass m traveling at a speed v is










1
2


m

v

2









{\displaystyle {\begin{smallmatrix}{\frac {1}{2}}mv^{2}\end{smallmatrix}}}
. In relativistic mechanics, this is a good approximation only when v is much less than the speed of light.
The standard unit of kinetic energy is the joule, while the English unit of kinetic energy is the foot-pound.

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  1. Amaterasu21

    At what size is kinetic energy no longer related to temperature?

    Hi all, I've read so many times that "temperature is a measure of the average kinetic energy of the molecules in a substance," or sometimes "particles" to encompass atoms and ions too. But how big can "molecules/particles" be before their kinetic energy is no longer relevant to temperature? If...
  2. S

    The location of the point with lowest kinetic energy

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  4. F

    B In a nuclear decay, is all of the released energy kinetic energy?

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  5. R

    Why is the kinetic energy equation multiplied by ½?

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  6. A

    Temperature is a measure of the average kinetic energy of a gas?

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  7. H

    A Degrees of freedom of thin rods

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  8. R

    Understanding Kinetic Energy, Angular Momentum & Torque

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    Physics momentum problem -- Collision between 2 blocks that stick together

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  11. K

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  12. J

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  13. F

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  14. M

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  15. T

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  16. T

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  17. F

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  19. kaloyan

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  20. A

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  21. A

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  23. B

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  24. EchoRush

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  26. T

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  32. M

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  33. A

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  34. J

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  35. P

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  36. Shivam

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  37. E

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  38. Nikhil Rajagopalan

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    Dear Experts, I have read from various sources that the temperature of a gas is related to the "average translational kinetic energy" of a molecule of gas. When there are molecules that support motion other than translational ,which may also have rotational and vibrational motion, How does those...
  39. H

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  41. L

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  42. greenrichy

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  43. H

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  44. D

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  45. A

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  47. lilymay992

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  48. M

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  49. O

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  50. E

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