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In Newtonian mechanics, momentum (pl.: momenta or momentums; more specifically linear momentum or translational momentum) is the product of the mass and velocity of an object. It is a vector quantity, possessing a magnitude and a direction.
In classical mechanics, impulse (symbolized by J or Imp) is the change in momentum of an object. If the initial momentum of an object is p 1, and a subsequent momentum is p 2, the object has received an impulse J: =. Momentum is a vector quantity, so impulse is also a vector quantity.
The joule (/ dʒ uː l / JOOL, or / dʒ aʊ l / JOWL; symbol: J) is the unit of energy in the International System of Units (SI). [1] It is equal to the amount of work done when a force of one newton displaces a mass through a distance of one metre in the direction of that force.
In SI units, mass is measured in kilograms, speed in metres per second, and the resulting kinetic energy is in joules. For example, one would calculate the kinetic energy of an 80 kg mass (about 180 lbs) traveling at 18 metres per second (about 40 mph, or 65 km/h) as
The moment of force, or torque, is a first moment: =, or, more generally, .; Similarly, angular momentum is the 1st moment of momentum: =.Momentum itself is not a moment.; The electric dipole moment is also a 1st moment: = for two opposite point charges or () for a distributed charge with charge density ().
The momentum of the famous football kick of the Brazilian player Roberto Carlos in the match against France in 1997. The football had a speed of 137 km/h (85 mph), making it one of the hardest kicks measured. 1300: 10 13 000: A four-door car weighing 1 300 kg (2 900 lb) crashing at 36 km/h (22 mph). 2000: 10 20 000
The joule-second is a unit of action or of angular momentum. The joule-second also appears in quantum mechanics within the definition of the Planck constant. [2] Angular momentum is the product of an object's moment of inertia, in units of kg⋅m 2 and its angular velocity in units of rad⋅s −1.
Measure for the ease with which an object resists conduction of heat K/W L −2 M −1 T 3 Θ: extensive Thermal resistivity R λ: Measure for the ease with which a material resists conduction of heat K⋅m/W L −1 M −1 T 3 Θ: intensive Viscosity: η: The measure of the internal friction in a fluid Pa⋅s L-1 M T-1: intensive, scalar Volume: V