# What is Unitless?

unitless (not comparable) (physics) Having no units of measurement; such as a ratio or percentage of two numbers which have the same units.

## Is a unitless quantity always dimensionless?

A unitless quantity will always be dimensionless as it has to be a ratio of quantities with the same dimensions.

## Can a unitless quantity exist?

When considering unitless quantities it is impossible for them to have any dimension, since a unitless quantity does not have dimensions. So the answer to the question is option (B)- Never has a non-zero dimension.

## What is Unitless value?

The property of a number as having no units of measurement, such as a ratio or percentage of two numbers which have the same units.

## Which of the following is not the name of a physical quantity?

There are only seven fundamental physical quantities, length, time, amount of substance, electric current, temperature, luminous intensity, and mass. Kilogram is not a physical quantity.

## Which quantities are dimensionless?

• Strain.
• Mass fraction.
• Molar fraction.
• Relative humidity.
• Mach number.
• Specific gravity.
• plane angle, solid angle.

## Is mole fraction unitless quantity?

Mole fraction is a unit of concentration, defined to be equal to the number of moles of a component divided by the total number of moles of a solution. Because it is a ratio, mole fraction is a unitless expression.

## Is energy a physical quantity?

Energy is a physical quantity that follows precise natural laws.

## Is angle a dimensionless quantity?

Yes, angles are dimensionless. Angle is a dimensionless quantity but it has units like degree, radian etc. Q. A dot is dimensionless.

## Can a quantity have dimensions but still be Unitless?

There is no physical quantity which has dimensions but no units because units are derived from the dimensional analysis itself.

## Is impulse a physical quantity?

Impulse is a vector quantity. Explanation: Impulse applied to an object produces an equivalent vector change in its linear momentum, also in the same direction. As the momentum is a vector quantity so the change in momentum is also a vector quantity.

## Is displacement a unitless quantity?

Displacement gradient is length per unit length. Hence it is unitless quantity.

## Which of the following is a Unitless dimensionless quantity?

Refractive index is the property of a material to bend light when passing through the medium. It is taken as the ratio of the speed of light in vacuum to the speed of the light in the given medium. Since it is the ratio of speed, it has no dimension or units. Then clearly D is the answer.

## Which of the following is Unitless constant?

Refractive index, poissonâ€™s ratio and relative density are the ratio of two similar physical quantities and therefore, these are dimensionless constants.

## Is density a dimensionless quantity?

Relative density is equal to the ratio of density of substance to density of water. Since both have the same dimensions, thus their ratio is dimensionless.

## Is stress a dimensionless quantity?

Because this is a ratio, therefore it is dimensionless quantity.

## Which is dimensionless quantity Mcq?

Correct option b StrainExplanation :Therefore strain is a dimensionless quantity.

No worries!

## Is time a physical quantity?

The Classical Perception of Physical Quantities The basic quantities are length, time, mass, charge, temperature, and the amount of substance.

## Is mass is a physical quantity?

Mass is a physical quantity of an object. Mass per acceleration of gravity gives us the weight of the object.

## Is velocity a dimensionless quantity?

Solution : Relative velocity has the dimensions of velocity and it can have any value. Hence it is a dimensional variable.

## What is dimensionless and example?

A dimensionless quantity is a physical quantity which has no physical units. Examples of dimensionless quantity are:- Strain is the ratio of the change in length to original length. Poissonâ€™s ratio is the ratio of lateral strain to longitudinal strain.

## Which physical quantity has no unit and no dimension?

Solution : Yes, for example, strain has no units and no dimensions.

## What is the unit of density?

Density is commonly expressed in units of grams per cubic centimetre. For example, the density of water is 1 gram per cubic centimetre, and Earthâ€™s density is 5.51 grams per cubic centimetre. Density can also be expressed as kilograms per cubic metre (in metre-kilogram-second or SI units).