There are three very important things to remember about velocity time graphs.
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The distance travelled is the area under the graph.
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The gradient is equal to the acceleration. If the graph issloping up – the gradient is positive – there is acceleration.If the gradient is negative – the graph is sloping down – thereis deceleration - the acceleration is negative.
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The average speed is equal to the total distance (the areaunder the graph) divided by the total time.
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If the speed is constant the graph is horizontal (thegradient is zero).
The above graph shows the motion of a car. The car travels with constant velocity
for the first second.The area under the graph is a trapezium. The distance travelled is equal to the area.
Between 1 and 5 seconds it decelerates :
There is deceleration of
