Question

The graph below shows relationship between speed and elapsed time for a car moving in a straight line what is the magnitude of the acceleration of the car

Answer 1

Answer:

$1.25 m/s^2$

Explanation:

The acceleration of an object is the rate of change of velocity of an object.

Mathematically, it is given by:

$a=\frac{\Delta v}{\Delta t}$

where

$\Delta v$ is the change in velocity

$\Delta t$ is the change in time

In this problem, we have a graph of the speed (which is equal to the velocity, since the motion is in a straight line) versus the time. Therefore, the slope of the graph is exactly equal to the acceleration of the object:

$a=\frac{\Delta v}{\Delta t}$

So, we can find the magnitude of the acceleration of the car by evaluating the slope of this line.

Taking the last point (12.0 s, 15.0 m/s) and the starting point (0 s, 0 m/s), we have:

$\Delta v=15.0 - 0 = 15.0 m/s\\\Delta t = 12.0 - 0 = 12.0 s$

So, the acceleration is:

$a=\frac{15.0}{12.0}=1.25 m/s^2$