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Mechanics Velocity against Time Graphs
The slope of a v/t graph represents acceleration. Using a v/t graph to find distance moved
Calculating the magnitude of the displacement of the body is numerically the same as calculating the area under the graph. Conclusion The Acceleration due to Gravity (Acceleration of Free Fall) Experiments show that, when air resistance can be ignored, all bodies fall with the same acceleration. This acceleration is given the symbol g.
The acceleration due to gravity is not exactly the same at all points on the earth’s surface. Small variations in g are due to:
Velocity against Time Graphs for a Falling Body
The force of air resistance increases as the velocity of the body increases. Therefore, a body will reach a terminal velocity (v_{t}) when air resistance is equal in magnitude to the weight of the body. 
