You can show journeys on distance-time graphs

If an object moves in a straight line, its distance travelled can be plotted on a distance-time graph

• Gradient=speed. This is because speed = distance / time

• Flat sections are where it’s stationary, it’s stopped

• Straight uphill sections mean it is travelling at a steady speed

• Curves represent acceleration or deceleration

• A steepening curve means it’s speeding up(increasing gradient)

• A levelling off curve means it’s slowing down

• If the object is changing speed you can find its speed at a point by finding the gradient of the tangent to the curve at that point

You can also show them on a velocity-time graph

How an object’s velocity changes as it travels can be plotted on a velocity-time graph

• Gradient = acceleration, since acceleration is change in velocity / time

• Flat sections represents travelling at a steady speed

• The steeper the graph, the greater the acceleration or deceleration

• Uphill sections are acceleration

• Downhill sections are deceleration

• A curve means <del>changing</del> acceleration

• The area under any section of the graph is equal to the distance travelled in that time interval

• If the section under the graph is irregular, it’s easier to find the area by counting the squares under the line and multiplying the number by the value of one square