Unit of Force - Definition, Unit, Types, Formula, FAQs

Q: Differentiate between dyne and Newton units of force.

Dyne Newton It is the unit of force in CGS (Centimeter – gram – second) system of units. It is the unit of force in SI (System International ) system of units. Its symbol is dyn Its newton symbol is N 1 dyne is defined as the force required to accelerate 1 gram of mass at an acceleration of 1 centimeter per second squared 1 Newton is defined as the force required to accelerate 1 kg of mass at an acceleration of 1 meter per second squared.

Edited By Vishal kumar | Updated on Sep 24, 2024 02:22 PM IST

What is unit?
The quantity which can be used as a standard of measurement is known as unit. For example: If we say, the length of the rod is 2 meter, then the numerical value is 2 and the unit of the length is meter.

What is the unit of force? Define SI unit of force.

As we know force is a physical quantity, it has to be measured. To measure any physical quantity, there is a standard of measurement known as unit of that quantity.

The term force is discovered and defined by Isaac Newton SI unit, that’s why the unit of force is named after him which is NEWTON. However, force measurement units can differ, depending upon the different systems of measurements such as C.G.S. , M.K.S which we read further in this article.

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Unit of Force - Definition, Unit, Types, Formula, FAQs

SI unit of force in physics

SI unit stands for System International unit. This system of the unit consists of seven basic units which are used to derive other units.

The SI unit of force is kg m/sec² which is termed, Newton.

Derivation of SI unit of force in physics

To derive the SI unit of force in physics, we need to remember the formula of force which is defined as

F= m× a

where F ? Force

m ? Mass

a ? Acceleration

First, we derive the SI unit of acceleration using its formula which is defined as

a=∆v/∆t

where ∆v ? Change in velocity

∆t ? Change in time

Now, we write the SI unit of velocity and time in the formula of acceleration

a=m/s²

Hence, the SI unit of acceleration

a= msec^-2

Now, we put the SI unit of acceleration and mass in the formula of force

F= kg× msec^-2

Hence, the SI unit of force is given as

F= kg msec^-2 or Newton

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Other unit of force
Other than SI unit, force is also measured in different units depending upon the system of measurements which are given below :

Dyne ?

Symbol - dyn

1 dyn=10^-5N

1 dyne is defined as the force can be measured by required accelerate of 1 gram of mass at an acceleration of 1 centimeter per second. It is the unit of force in CGS (Centimeter – gram – second ) system of units and it is primarily used in measuring surface tension.

Gram- force ?

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Symbol - gf

1 gf=0.0098 N

1 gram- force is defined as the force required to accelerate 1 gram of mass at acceleration equal to the acceleration due to gravity. It is the gravitational unit of force in CGS (Centimeter – gram – second ) system of units.

Poundal ?

Symbol - pdl

1 pdl= 0.1382 N

1 Poundal is defined as the force required to accelerate 1 pound of mass at an acceleration of 1 foot per second. It is the unit of force in the FPS ( Foot – pound – second ) system of units and this system is commonly used in civil engineering and construction engineering.

Also read :

Pound- force ?

Symbol - lbf

1 lbf=4.448222 N

1 pound force is defined as the force required to accelerate 1 pound of mass at an acceleration equal to the acceleration due to gravity. It is the unit of force in FPS ( Foot – pound – second ) system of units and this is also used in civil engineering and construction engineering.

Kilogram-force ?

Symbol - kgf

1 kgf=9.806650 N

1 Kilogram-force is defined as the force required to accelerate 1 kilogram of mass at an acceleration equal to the acceleration due to gravity. It is the unit of force in MKS ( Meter – kilogram – second ) system of units and this system is also known as metric system.

Sthène ?

Symbol - sn

1 sn= 1000 N

1 Sthène is defined as the force required to accelerate 1 metric ton (1000 Kilograms) of mass at an acceleration of 1 meter per second. It is the unit of force in MTS ( metre–tonne–second ) system of units.

Kip ?

Symbol - kip

1 kip= 4.44822 kN

1 kip is defined as 1000 pound-force. It is used in engineering, primarily in civil engineering to measure engineering loads.

Also check-

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Frequently Asked Questions (FAQs)

1. Define unit and write SI unit of force ?

The standard of measurement of a physical quantity is known as unit. The SI unit of force is kg m/sec^2 which is termed as Newton.

2. What are the various units of force?

Other than the SI unit that is Newton, force is also measured in other units. Some of them are

Dyne
Gram – force
Poundal
Pound – force
Kilogram – force
Sthène

3. Define 1 dyne of force.

1 dyne is defined as the force required to 1 gram of mass at an acceleration of 1 centimeter per second squared. It is the unit of force in CGS ( Centimeter – gram – second ) system of units.

4. Derive the unit of force in SI system.

To derive the SI unit of force, we write the SI unit of other physical quantities in the formula of force which is

F= m× a

where, m - Mass

a - Acceleration

So, F= kg× msec^{-2}

[ As SI unit of acceleration is msec2 and SI unit of mass is kg ]

or Newton

Hence derived unit of force or the SI unit of force is Newton

5. Differentiate between dyne and Newton units of force.

Dyne	Newton
It is the unit of force in CGS (Centimeter – gram – second) system of units.	It is the unit of force in SI (System International ) system of units.
Its symbol is dyn	Its newton symbol is N
1 dyne is defined as the force required to accelerate 1 gram of mass at an acceleration of 1 centimeter per second squared	1 Newton is defined as the force required to accelerate 1 kg of mass at an acceleration of 1 meter per second squared.