All pure numbers are dimensionless quantities, for example
1, i, π, e, and φ
. Units of number such as the dozen, gross, googol, and Avogadro’s number may also be considered dimensionless.
Which of the following is not a dimensionless number?
The Questions and Answers of Which of the following is not a dimensionless number? a)the coefficient of lift, CLb)the pipe friction factor, fc)the Manning’s coefficient, Nd)
the coefficient of discharge
, CdCorrect answer is option ‘C’.
What makes a number dimensionless?
A number representing a property of a physical system, but not measured on a scale of physical units (as of time, mass, or distance)
. Drag coefficients and stress, for example, are measured as dimensionless numbers.
How do you find a dimensionless number?
(In the table, the diagonals give common symbols for the quantities, and the given dimensionless number is
the ratio of the left column quantity over top row quantity
; e.g. Re = inertial force/viscous force = vd/ν.)
Which one is the dimensionless quantity?
In dimensional analysis, a dimensionless quantity is a quantity to which no physical dimension is assigned, also known as a
bare
, pure, or scalar quantity or a quantity of dimension one, with a corresponding unit of measurement in the SI of the unit one (or 1), which is not explicitly shown.
Is refractive index a dimensionless quantity?
v is the velocity of light in that particular medium. c is the velocity of the light in vacuum. So, we can say that the refractive index is a
dimensionless quantity
.
Is Reynolds number dimensionless?
The Reynolds number is
a dimensionless number
. High values of the parameter (on the order of 10 million) indicate that viscous forces are small and the flow is essentially inviscid. The Euler equations can then be used to model the flow.
What is the use of dimensionless numbers?
Dimensionless numbers
reduce the number of variables that describe a system
, thereby reducing the amount of experimental data required to make correlations of physical phenomena to scalable systems.
What does Prandtl number tell us?
Prandtl number signifies the thickness of thermal boundary layer and thickness of hydrodyanamic boundary layer, depending on whether it is equal to one, or more than one or less than one. … Tells us
the relative thickness of thermal boundary layer to momentum boundary layer
.
Which is the dimensionless constant?
In physics, a dimensionless physical constant is a physical constant that is dimensionless, i.e. a
pure number having no units attached
and having a numerical value that is independent of whatever system of units may be used.
What is Nusselt number formula?
the Nusselt number, which is
Nu
Dh
= 890
. the hydraulic diameter of the fuel channel is: D
h
= 13,85 mm. the thermal conductivity of reactor coolant (300°C) is: k
H2O
= 0.545 W/m.K. the bulk temperature of reactor coolant at this axial coordinate is: T
bulk
= 296°C. the linear heat rate of the fuel is: q
L
= 300 W/cm (F
Q
≈ …
What is K in Nusselt number?
In the case of the Biot number, k is the thermal conductivity of the solid. In the case of the Nusselt number, k is
the thermal conductivity of the fluid flowing around the body.
How do you show something is dimensionless?
In terms of your symbols, in many branches of physics it is common to use
a “hat”
, “tilde” or “star” notation above a symbol to indicate that it is a dimensionless quantity.
Is stress is a dimensionless quantity?
Hint: We can define stress as the reactive force per unit area. Mathematically it is defined as the ratio of force and area of cross-section. Keeping the characteristics of stress in mind we will find the correct option.
Is specific heat a dimensionless quantity?
Like specific gravity, specific heat is a
dimensionless quantity
, i.e., a pure number having no unit of measurement associated with it.
Is Young’s modulus dimensionless?
It is
a dimensionless quantity
. So, the units of young’s modulus will be the same as that of stress developed.
