 > > > Average Acceleration Formula

# Average Acceleration Formula

Acceleration is a very familiar term you must have definitely heard of especially relating to cars. When the velocity of an object changes, we say it is accelerating. Thus, acceleration is the rate of change of velocity with time. In layman’s term, we use acceleration to describe a state of increasing speed. Similar to velocity, there are two kinds of acceleration which are average and instantaneous. Average acceleration is determined over a long interval of time. When we use the word long over here, we use it in the context of finite i.e. anything with a beginning and an end. Thus, this article will focus on average acceleration formula.

## Definition

Average acceleration refers to the rate at which the velocity changes. We divide the change in velocity by an elapsed time to find out the average acceleration of anything.

For instance, if the velocity of a crazy ball increases from 0 to 60 cm/s in 3 seconds, the average acceleration of the ball would be 20 cm/s/s. Therefore, it means that the velocity of the marble will increase by 20 cm/s every second. The table given below will help you understand better the operation:

 Time (Seconds) Velocity (cm/s) 0 0 1 20 2 40 2 60 4 80

Therefore, we see that average acceleration is described as the ratio of change in velocity to the change in time for a specified interval. Contrasting instantaneous acceleration, the average acceleration is calculated for a specified interval.

Get the huge list of Physics Formulas here

### Formula

When we talk about acceleration, we see that it is the rate of change for velocity. In other words, it is the change in velocity over a particular period of time. Similarly, the average acceleration is the final velocity minus the initial velocity per time is taken. Therefore, the formula for average acceleration formula is:

Aavg = Δv / Δt

Over here:

Aavg refers to the average acceleration, m/s2

Δv is vf – vi, m/s

Δt refers to tf – ti, s

## Solved Examples for You

Question- Your sister just bought a new car which goes from 0 to 60 m/s in just 7 seconds. Calculate the acceleration of the car.

Answer- First, we will work with what we have. Thus, we have been given the final velocity which is vf = 60 m/s along with the initial velocity which is vi = 0. Further, our final time is tf = 7 sec in addition to the initial time which is ti = 0. Therefore, when we apply the average acceleration formula, we get:

Aavg = Δv / Δt

Aavg = (60 m/s) / 7 s

Aavg = 12.86 m/s2

Therefore, the acceleration of the car is 12.86 m/s2.

Question- A bus driver is driving along a side-road at 45 m/s when suddenly he encounters a puppy run across the street. Thus, he rapidly slows down to 3 m/s within a time span of 1.5 sec. Calculate the acceleration of the bus.

Answer- Placing the figures in the equations, we will see that we have our final velocity as vf = 3 m/s and our initial velocity, vi = 45 m/s. In addition to the time we have, t = 1.5 sec. Therefore, by applying the average acceleration formula, we will get:

Aavg = Δv / Δt

Aavg = (3 m/s – 45 m/s) / 1.5 sec

Aavg = (- 42 m/s) / 1.5 sec

Aavg = – 28 m/s2

Therefore, the acceleration of the bus is -28 m/s2. It is important to note over here that the negative sign indicates the slowing down of the object.

Share with friends

## Customize your course in 30 seconds

##### Which class are you in?
5th
6th
7th
8th
9th
10th
11th
12th
Get ready for all-new Live Classes!
Now learn Live with India's best teachers. Join courses with the best schedule and enjoy fun and interactive classes.  Ashhar Firdausi
IIT Roorkee
Biology  Dr. Nazma Shaik
VTU
Chemistry  Gaurav Tiwari
APJAKTU
Physics
Get Started Subscribe
Notify of

## Question Mark?

Have a doubt at 3 am? Our experts are available 24x7. Connect with a tutor instantly and get your concepts cleared in less than 3 steps. 