Question

1 newton=_______dyne.
(a). 103
(b). 107
(c). 105
(d). 108

Answer 1

- Hint: Convert the SI unit into CGS unit of force (i.e. convert kg m ${s}^{-2}$ into its CGS equivalent).

Complete step-by-step solution -

In physics, the dyne is a unit of force specified in the centimetre-gram-second (cgs) system of units, symbol "dyn". One dyne is equal to exactly 10 -5 newtons. Further, the dyne can be defined as "the force required to accelerate a mass of one gram at a rate of one centimetre per second squared."
Derivation:
     1newton = 1kg m ${ s }^{ -2 }$
    =>1newton = (1000gm×100cm) ${ s }^{ -2 }$
 =>1newton = 100000 $g cm { s }^{ -2 }$
∴ 1newton = ${ 10 }^{ 5 }$ dynes

ADDITIONAL INFORMATION:

DYNE: The dyne (symbol dyn,) is a derived unit of force specified in the centimetre–gram–second (CGS) system of units, a predecessor of the modern SI.
The name dyne was first proposed as a CGS unit of force in 1873 by a Committee of the British Association for the Advancement of Science.
The dyne is defined as "the force required to accelerate a mass of one gram at a rate of one centimetre per second squared".An equivalent definition of the dyne is "that forces which; acting for one second, will produce a change of velocity of one centimeter per second in a mass of one gram".

NEWTON: The Newton is the International System of Units (SI) derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. One Newton is the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force.
One Newton is the force needed to accelerate one kilogram of mass at the rate of one metre per second squared
in the direction of the applied force. The units "metre per second squared" can be understood as change in velocity per time, i.e. an increase of velocity by 1 metre per second every second.
In 1946, Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate of 1 metre per second squared. In 1948, the 9th CGPM Resolution 7 adopted the name Newton for this force.] The MKS system then became the blueprint for today's SI system of units. The Newton thus became the standard unit of force in the Système international d'unités (SI), or International System of Units.

Note :- Newton is the basic unit of force used while dyne is a derived unit. Don’t confuse yourself between dyne and Newton and remember the relation since it is used in many questions.