# Equation: Calculation of Speed

## Definition

• Speed is a measure of how quickly an object moves in a certain period of time.
• The formula to calculate speed is Speed = Distance ÷ Time.

## Key Points

• The equation can be rearranged to find either distance (Distance = Speed x Time) or time (Time = Distance ÷ Speed”), depending on what information is given and what is being asked.
• If you are given the distance travelled and the time taken to travel, you can use the basic formula Speed = Distance ÷ Time to calculate speed.
• When the speed is constant, it is known as uniform speed.

## Units

• When using the formulas, ensure the units are compatible. For instance, if the distance is given in meters and the time in seconds, the speed will be in meters per second (m/s).
• Similarly, if the distance is given in miles and the time in hours, the speed will be in miles per hour (mph).
• Remember to always include the units in your final answers to avoid losing marks.

## Examples

• If you know a car travelled a distance of 120km in 2 hours, its speed can be calculated as speed = 120km ÷ 2h = 60 km/h.
• If a runner completes a 100m race in 10 seconds, their speed is speed = 100m ÷ 10s = 10 m/s.

## Real-life Applications

• Understanding speed calculations is important in various real-life scenarios, such as figuring out traveling times, calculating fuel efficiency, and in sports analytics.
• It’s also instrumental in several fields of applied science, including physics, engineering, and astronomy.