The **mass flow rate** is defined as the **mass of a liquid substance passing per unit of time**. SI units are kilogram per second. The mass flow directly depends on the density, velocity of the liquid, and the area of the cross-section. It is also defined as the movement of mass per unit of time.

Index

**Formula for Mass Flow Rate**

The formula can be written as,

\(m = \rho VA\)Where,

\(\rho\) – Density of fluid

\(V\) – Velocity of liquid

\(A\) – Area of cross section

**Solved Examples**

**Question 1. **Given the density of a fluid as 1000 kg/m^{3}, velocity as 50 m/s and area of cross-section as 10 cm^{2}, determine the movement of mass per unit of time.

**Solution.** Given,

⍴= 1000 kg/m^{3}

V = 50 m/s

A = 10 cm^{2} = 0.1 m^{2}

m = ⍴VA

m = 1000 x 50 x 0.1

∴ m = 5000 kg/s

**Question 2.** A fluid moves at 20 m/s through a tube. The tube has an area of 0.5 m^{2}. The density of the fluid is 1.5 g/m^{3}. Determine the movement of mass per unit of time.

**Solution.** Given,

⍴= 1.5 g/m^{3}

V = 20 m/s

A = 0.5 m^{2}

m = ⍴VA

m = 20 x 1.5 x 0.5

∴ m = 15 g/s

**FAQs**

**How do you calculate mass flow rate?**It can be calculated by formula:

m = ⍴VA

Where,

⍴ – Density of fluid

V -> Velocity of liquid

A -> Area of cross section

**What are mass flow rate and volumetric flow rate?**Mass flow rate is the mass of a liquid passing through an area of cross-section per unit of time. Volumetric flow rate is the volume of the liquid passing through per unit of time.

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