# What is constant acceleration?

## Meaning of Constant Acceleration

Constant acceleration is when the **rate at which the speed** or velocity of a body changes, how much it increases or decreases, stays the same for a given period of time.

The definition of acceleration is the **rate** at which the velocity of an object changes.

**Acceleration** = **Change in velocity** ÷ Time

Therefore, constant acceleration means that the **object gets faster** or slower at the same speed; the same speed change for a defined period of time.

Acceleration, velocity, and displacement are the three **main quantities** that describe the motion of a body.

Displacement is a measure of the distance a body travels **.**

Velocity describes how **fast the body travels** , how far it travels during a specific period of time.

Acceleration is a measure of the **change in velocity** , that is, how the velocity of a body changes at a given moment.

Isaac Newton was the first to link **acceleration to force** .

Newton ‘s **second law of motion** states that the force acting on a body (F) can be described in terms of its mass (m) and its acceleration (a) by the equation F = ma.

This means that a **body subjected to a** constant force will experience a constant acceleration.

The metric unit of force is called the Newton (N), and a force of 1 Newton will cause a 1 kg body to accelerate at 1 m per second per second (ms2).

This means that, from a point of rest, after one second the body will be moving at 1 m per second, and after 10 seconds it will be moving at 10 m per second.

Any object that is influenced by gravity is **constantly accelerating** .

Newton supposedly invented his **theory of gravity** when an apple fell next to him while he was sitting under a tree.

Whether this story is true is not known, but what is known is that Newton deduced that an apple falls due to a force acting between the Earth and the apple, and that this force is the result of their respective masses.

Before Newton, it was generally thought that heavier objects fall faster than lighter ones. A heavy stone falls faster than a light feather, but it has nothing to do with their respective masses.

Calculating the **acceleration** caused by gravity on Earth depends on the radius of the object, its mass, and a number known as the gravitational force constant.

At the Earth’s surface, all objects experience a constant rate of acceleration of about 9.81 ms2, although this changes slightly with latitude, because the Earth is not a perfect sphere.

The **differences in motion** between a feather and a rock as they fall are caused by the frictional force of air particles acting on them.

This force opposes gravity and is the result of their shapes and not their masses. A feather is subject to much more friction with the air than a rock.

On the Moon, where there is no atmosphere, the two objects fall at the same rate.

## When is acceleration constant?

Constant acceleration refers to motion in which the speed of the object increases by the same amount per unit of time.

The most notable and important example of constant acceleration is **free fall** .

When an object is thrown, it experiences a **constant acceleration** due to gravity, which has a constant value of .

## summarizing

Acceleration describes how the **speed of an object changes** over time. (A=v/t).

For example, if a car increases its speed by 10 mph per second, it is accelerating. If the driver sees a red light, he hits the brakes, slowing down the cars, this would be an **example of deceleration** .

**Constant acceleration** can be determined by finding the slope of a graph of velocity versus time .

The most common example of **constant acceleration** is free fall. Neglecting air resistance, objects will fall to Earth with an acceleration of 10 m/s/s. This is the **effect of ****gravity** .

A useful ratio in free fall is distance equal to half gravity times time squared. distance = 1/2 (10m/s/s) (time)^2.

Acceleration is **any change in motion** . Speeding up, slowing down, changing direction are examples of acceleration.