Scientists often make measurements. The physical quantities they measure fall into two categories: scalars and vectors. Scalar and vector quantities are treated differently in calculations.

Part of

If initial velocity and final velocity are known, average velocity can be calculated using the equation:

**Average velocity** =

- Question
A school bus is travelling at 4 m/s.

Its velocity then increases to 12 m/s.

Calculate the average velocity of the bus over the journey.

Final velocity = 12 m/s.

Initial velocity = 4 m/s.

Average velocity =

= (4 m/s + 12 m/s) ÷ 2 = 16m/s ÷ 2 = 8 m/s.

The average velocity of the bus is 8 m/s.

**There are two equations for average velocity:**

Average velocity =

Average velocity =

**You decide which equation to use, depending on the quantities given in the question.**