How do you calculate speed?

Speed is calculated by dividing the distance travelled by the time taken to travel that distance.

To calculate speed, you use the formula:

\[ \text{Speed} = \frac{\text{Distance}}{\text{Time}} \]

This means you take the total distance an object has moved and divide it by the total time it took to move that distance. The units you use for distance and time will determine the units for speed. For example, if distance is measured in metres (m) and time in seconds (s), the speed will be in metres per second (m/s).

Let's break it down with an example. Imagine you walk 100 metres in 20 seconds. Using the formula:

\[ \text{Speed} = \frac{100 \text{ m}}{20 \text{ s}} = 5 \text{ m/s} \]

So, your speed would be 5 metres per second.

It's important to note that speed is a scalar quantity, which means it only has magnitude and no direction. This is different from velocity, which is a vector quantity and includes both magnitude and direction.

In everyday life, you might be more familiar with speed in kilometres per hour (km/h) or miles per hour (mph). The same formula applies, but you need to ensure that the distance and time units are consistent. For instance, if you drive 150 kilometres in 3 hours, your speed would be:

\[ \text{Speed} = \frac{150 \text{ km}}{3 \text{ h}} = 50 \text{ km/h} \]

Understanding how to calculate speed is fundamental in physics as it helps you analyse motion and understand how objects move in different contexts.