Question

An automobile accelerates from 20 m/s to 50 m/s in 5.0 seconds what is its acceleration

Answer 1

|Acceleration| = (change in speed) / (time for the change)

Change in speed = (50m/s - 20m/s) = 30 m/s
Time for the change = 5.0 sec

|Acceleration| = (30 m/s) / (5 sec) = 6 m/s² .

I wrote 'Acceleration' with absolute value lines ( | | ) around it,
because acceleration is actually a vector . . . it should have a
direction as part of its description. But we don't know anything
about its direction, so we can only talk about its magnitude (size).

Answer 2

Acceleration is a vector quantity that describes an object's rate of change in velocity.

Given
Vi = 20m/s
Vf = 50m/s
t = 5 s

Hence, a = vf – vi / t.


Solution:
A = 50 m/s – 20 m/s / 5s
A = 6m/s^2