# Question #4d1df

Oct 25, 2017

#### Answer:

The acceleration is $0.44 \frac{m}{s} ^ 2$

#### Explanation:

Acceleration is the ratio of the change in velocity of an object to the time required to produce that change:

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

In this problem, the change in speed was an increase from 20 m/s to 40 m/s - a change of 20 m/s.

It took from 15 s until 60 s to bring about this change, so 45 s elapsed.

Therefore the acceleration is the value of the ratio

$a = \frac{20 \frac{m}{s}}{45 s} = 0.44 \frac{m}{s} ^ 2$