# Continuity Equation for Mass

This formula states that the mass entering a system is equal to the mass leaves the system both at the same rate.

## Continuity Equation for Mass formula

\(\large{ A_1 \; v_1 = A_2 \; v_2 }\) |

### Where:

\(\large{ A_2 }\) = final area cross-section

\(\large{ A_1 }\) = initial area cross-section

### \(\large{ v_2 }\) = final cross-section velocity

\(\large{ v_1 }\) = initial cross-section velocity