# Mass

on . Posted in Classical Mechanics

Mass, abbreviated as m, is the amount of matter an object has.  It is the property of a body that causes it to have weight in a gravitational field.  It is sometimes used interchangeably in place of weight.  Mass is a scalar quantity having magnitude and is independent of any specific direction.

Weight is a vector quantity that depends on the gravity at a specific location.  The mass of an object is different from its weight, which is the force exerted on the object by gravity.  Mass is a fundamental property of matter, whereas weight is dependent on the object's mass and the acceleration due to gravity.

## Mass Types

• Gravitational Mass  -  The mass of an object as measured by its interaction with gravity, it is equal to its inertial mass.
• Invariant Mass  -  The inferred value of the mass is independent of the reference frame in which the energies and momentum are measured so that the mass is invariant.
• Mass Diffusivity  -  A proportionality constant between the molar flux due to molecular diffusion and the gradient in the concentration of the species.
• Molar Mass  -  The mass of a given compound equal to its molecular mass in gram.
• Relativity Mass  -  The mass of a body in motion relative to the observer.
• Rest Mass  -  Rest mass of a body is measured when the body is at rest and motionless and is also relative to an observer moving or not moving.

## Mass formula

$$\large{ m = \rho \; V }$$

### Mass - Solve for m

$$\large{ m = \rho \; V }$$

 density, ρ volume, V

### Mass - Solve for ρ

$$\large{ \rho = \frac{ m }{ V } }$$

 mass, m volume, V

### Mass - Solve for V

$$\large{ V = \frac{ m }{ \rho } }$$

 mass, m density, ρ

Symbol English Metric
$$\large{ m }$$ = mass $$\large{lbm}$$ $$\large{kg}$$
$$\large{ \rho }$$   (Greek symbol rho) = density $$\large{\frac{lbm}{ft^3}}$$ $$\large{\frac{kg}{m^3}}$$
$$\large{ V }$$ = volume $$\large{ft^3}$$ $$\large{m^3}$$

Tags: Mass Equations Types