The newton-second (also newton second; symbol: N⋅s or N s)
is the unit of
impulse in the
International System of Units
The International System of Units, internationally known by the abbreviation SI (from French ), is the modern form of the metric system and the world's most widely used system of measurement. It is the only system of measurement with official s ...
(SI). It is
dimensionally equivalent to the
momentum
In Newtonian mechanics, momentum (: 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. ...
unit kilogram-metre per second (kg⋅m/s). One newton-second corresponds to a one-
newton force applied for one
second
The second (symbol: s) is a unit of time derived from the division of the day first into 24 hours, then to 60 minutes, and finally to 60 seconds each (24 × 60 × 60 = 86400). The current and formal definition in the International System of U ...
.
:
It can be used to identify the resultant velocity of a mass if a force accelerates the mass for a specific time interval.
Definition
Momentum is given by the formula:
:
*
is the
momentum
In Newtonian mechanics, momentum (: 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 newton-seconds (N⋅s) or "kilogram-metres per second" (kg⋅m/s)
*
is the
mass
Mass is an Intrinsic and extrinsic properties, intrinsic property of a physical body, body. It was traditionally believed to be related to the physical quantity, quantity of matter in a body, until the discovery of the atom and particle physi ...
in
kilogram
The kilogram (also spelled kilogramme) is the base unit of mass in the International System of Units (SI), equal to one thousand grams. It has the unit symbol kg. The word "kilogram" is formed from the combination of the metric prefix kilo- (m ...
s (kg)
*
is the
velocity
Velocity is a measurement of speed in a certain direction of motion. It is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of physical objects. Velocity is a vector (geometry), vector Physical q ...
in
metres per second (m/s)
Examples
This table gives the magnitudes of some momenta for various masses and
speed
In kinematics, the speed (commonly referred to as ''v'') of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a non-negative scalar quantity. Intro ...
s.
See also
*
Power factor
*
Newton-metre –
SI unit of
torque
*
Orders of magnitude (momentum) – examples of momenta
References
Classical mechanics
SI derived units
Units of measurement
{{Measurement-stub