Two points on a velocity time-graph have coordinates (5s, 10ms-1) and (20s, 20ms-1). Calculate the mean acceleration between the two points
Answer Details
To calculate the mean acceleration between the two points, we need to find the change in velocity and the time taken for that change.
Change in velocity = final velocity - initial velocity
Here, the initial velocity is given as 10 ms-1 and the final velocity is given as 20 ms-1.
Change in velocity = 20 ms-1 - 10 ms-1 = 10 ms-1
The time taken for this change is given by the difference in time coordinates of the two points.
Time taken = final time - initial time
Here, the initial time is given as 5s and the final time is given as 20s.
Time taken = 20s - 5s = 15s
Now, we can calculate the mean acceleration using the formula:
Mean acceleration = change in velocity / time taken
Mean acceleration = 10 ms-1 / 15s = 0.67 ms-1
Therefore, the correct option is 0.67ms-1.
In simple terms, the mean acceleration between two points on a velocity-time graph is the average rate of change of velocity over that interval of time. It tells us how much the velocity changes on average per unit time.