Difference between revisions of "Kinetic Energy"
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'''Kinetic energy''' represents the [[energy]] asociated with the [[motion]] of an object.<ref>Serway and Beichner, ''Physics for Scientists and Engineers'', Fifth Edition</ref> It is defined as: | '''Kinetic energy''' represents the [[energy]] asociated with the [[motion]] of an object.<ref>Serway and Beichner, ''Physics for Scientists and Engineers'', Fifth Edition</ref> It is defined as: | ||
| − | K ≡ [[mass|m]][[velocity|v]]<sup>2</sup> / 2 | + | K ≡ [[mass|m]][[velocity|v]]<sup>2</sup> / 2 for a point mass and <math> K = {1 \over 2}mV^2 + {1 \over 2} I \omega ^2 </math> for a body, where I is the body's moment of inertia and omega is the body's angular velocity. |
The change of kinetic energy in an object is equal to the total [[work]] done on it by a [[force]]. In the case of constant force, this can be expressed as: | The change of kinetic energy in an object is equal to the total [[work]] done on it by a [[force]]. In the case of constant force, this can be expressed as: | ||
Revision as of 04:18, November 8, 2007
Kinetic energy represents the energy asociated with the motion of an object.[1] It is defined as:
K ≡ mv2 / 2 for a point mass and <math> K = {1 \over 2}mV^2 + {1 \over 2} I \omega ^2 </math> for a body, where I is the body's moment of inertia and omega is the body's angular velocity.
The change of kinetic energy in an object is equal to the total work done on it by a force. In the case of constant force, this can be expressed as:
ΣW = ΔK = mvf2 / 2 - mvi2 / 2
Where vi is speed at t = 0 and vf is speed at time = t.
Kinetic energy is a scalar and has the same units as work (i.e. Joule).
References
- ↑ Serway and Beichner, Physics for Scientists and Engineers, Fifth Edition