Speed

In this chapter we’re going to be exploring speed, we shall explore the formulae connecting speed, distance and time.

What is speed?

Speed is how fast an object is travelling. There is a variety of units in which we can measure speed. Speed can be measured in.

Each of the above units refers to the distance an object covers in a unit of time, for example the car below travels a distance of 50 miles in ½ hour.
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Speed would be the measure of the distance the car travels in one unit of time. The car travels 100 miles in one hour (100mph)
To work out speed we need to know the distance an object travels in one unit of time. To calculate speed we divide the distance travelled by the time taken. Therefore the speed formula is;

Average Speed

In some scenarios it would be impossible to measure the speed of an object accurately. In this case we measure average speed for example a car travels 36 miles in heavy traffic for 2 hours. The average speed is;

The car’s speed during the journey could have been faster or slower that the average speed.

Distance

We can work out the distance an object travels by using the speed formula. We rearrange it to make distance the subject.
Distance is how far and object travels each second multiplied by the number of seconds travelled for (time) The following formula describes this;

For example an athletic runs at 8m/s. How far does he go in 6 seconds?

Time taken

Again we can find out time taken by an object to travel a certain distance by rearranging the speed formula.

Example

A plane is capable of travelling 600mph. How long will it take to travel 3000 miles.
We find the time taken by dividing distance by how far the plane would travel each hour. The formula for time taken is shown below.

We can use this formula to find time taken.

It takes the plane 5hrs to travel 3000miles.