In a graph we will represent about the speed of cars on a open road
To find speed we have to follow , Speed = Gradient of distance - time graph
Distance travelled / km Time taken / h
0 0.0
10 0.4
20 0.8
100 1.8
110 2.3
To calculate speed we have to follow Speed = Gradient of distance - time graph
Calculating Acceleration
These are not very convenient units, although they may help to make it clear what is happening when we talk about acceleration. To calculate an object’s acceleration, we need to know two things:
its change in velocity (how much it speeds up).
the time taken (how long it takes to speed up).
The acceleration of the object is defined as the change of an object’s velocity per unit time.
Acceleration = Change in velocity / Time taken , A =ΔV / ΔT.
In the example of the express train, we have initial velocity u = 0 km/h, final velocity v = 300 km/h and time taken t = 300 s.
So, acceleration A =300 km/h−0 km/h divided by 300 s = 1 km/h per
second. Worked Example 2.7 uses the more standard velocity units of m/s.