Definition of newton
A newton is the force required to give a mass of 1 kilogram (1 kg) an acceleration of 1 meter per second per second (1 m/s2). It is abbreviated as N.
This unit of measurement is in the metric or SI system and is used in scientific work more than other units of force.
1 N is equivalent to 1 kg-m/s2.
Applications of the newton
The newton combined with other measurements is used in various applications.
Moment of force
The unit of torque or moment of force is the newton-meter (N-m), where m is the moment arm.
Energy, work and heat
The newton-meter (N-m) is also the definition of the joule (J), which is a unit of energy. It can be seen that the units of kinetic energy E = ½mv2 are in kilogram-meter2/seconds2 and kg-m2/s2 = N-m.
Power and radiant flux
Power is energy per second or N-m/s, with the unit of watt. This is also the unit for radiant flux or power from electromagnetic radiation.
Pressure
The unit of pressure is the pascal (P), which is the force per unit area (N-m2).
Other units of force
There are other units of force, not as commonly used as the newton.
Dyne
A dyne is the force required to give a mass of 1 gram (1 g) an acceleration of 1 centimeter per second per second (1 cm/s2). 1 N = 100,000 dynes.
You might use the dyne, if working with small objects.
Poundal and pound
A poundal is the force required to give a mass of 1 pound (1 lb) an acceleration of 1 foot per second per second (1 ft/s2). 1 poundal equals 0.1382 newtons.
A pound is the force applied on a mass of 1 pound (1 lb) by the acceleration due to gravity. It is a non-technical unit of force and is also called the weight.
These units of force are in the English system and are seldom used in scientific measurements.
Summary
A force acts on an object to change its velocity or direction. In most scientific work, force is designated as a newton (N) in the metric or SI system of measurement. The newton has applications in various scientific measurements. There are other units, not used as often.