The meaning of velocity for an object is the rate at which the object’s position changes in relation to a frame of reference and time. It may sound difficult, but velocity simply refers to the rate at which something moves in a given direction.

It is a vector quantity, which means that to define velocity, we need both magnitude (speed) and direction. It has the SI unit of meter per second (ms-1). When the amount or direction of a body’s velocity changes, the body is said to be accelerating.

Velocity and Acceleration

Difference between Velocity and Acceleration
Image: Unsplash

To put it another way, it’s the amount of displacement created per unit of time.

 Velocity = Displacement / Time 

        = x / t

Where x is the displacement or the distance travelled in a given direction. The difference between the positions is used to calculate it.

x = Final point – Initial point 

   = v – u 

t, distance travelled in time.

V = d / t 

Initial and Final Velocity 

When gravity first exerts a force on an object, its initial velocity indicates how fast it travels. The final velocity, on the other hand, is a vector number that measures a moving body’s speed and direction after it has reached its maximum acceleration.

With a few calculations and some basic conceptual knowledge, determining the final velocity is simple.

  • Divide the time it took the object to go a particular distance by the total distance to determine the object’s original velocity. V is the velocity, d is the distance, and t is the time in the equation V = d/t.
  • Calculate the object’s acceleration by dividing its mass by the force and multiplying the result by the amount of time it took to accelerate. For example, if the object weighs 30 kg and is subjected to a force of 15 N, the acceleration is 4 m/s.
  • To calculate the ultimate velocity, add the amounts from Steps 1 and 2. If your initial velocity was 3 m/s and your object acceleration was 4 m/s, your end velocity would be 7 m/s (3 + 4 = 7).


Acceleration is the angry, fire-breathing dragon of motion variables as compared to displacement and velocity. It can be violent; some people are afraid of it; and, if it’s large enough, it makes you pay attention. You’re accelerating while you’re sitting in a plane during take-off, slamming on the brakes in a car, or turning a corner at a fast speed in a go-kart.

Any process in which the velocity varies is referred to as acceleration. Because velocity is both a speed and a direction, you can only accelerate in one of two ways: alter your speed or change your direction—or both.

The rate at which velocity changes over time is called acceleration. This is a vector quantity with both a direction and a magnitude, similar to velocity. Acceleration is the phrase used to describe a rise in velocity, whereas deceleration is used to describe a reduction in velocity. A change in direction at a constant speed is still termed acceleration since velocity encompasses both a direction and a speed. Acceleration can be simply defined as: 

Acceleration= time taken for velocity to change/ change in velocity

​Acceleration is measured in terms of distance/time squared, such as meters/second2.

Constant Acceleration vs Constant Velocity  

When you travel at a constant velocity, you keep moving in the same direction at the same speed. You have zero acceleration if your velocity remains constant. Imagine driving along a straight road while maintaining the same speed on your speedometer.

A constant acceleration, on the other hand, is entirely different. Your velocity will always change if you move at a constant acceleration, but it will change by the same amount every second. You may envision dropping something from a building because the acceleration due to gravity on Earth is constant at 9.8 m/s2. The initial velocity is minimal, but it increases by 9.8 meters per second as it falls under gravity.

What is the difference between velocity and acceleration?

Velocity is the rate of change of displacement.Acceleration is the rate of change of velocity.
The SI unit of velocity is m/s or ms–1.The SI unit of acceleration is m/s2 or ms–2.
Since it has both magnitude and direction, velocity is considered a vector quantity.Because it is simply the rate of change of velocity, acceleration is also a vector quantity. 
Velocity can be positive or negative or zero.Acceleration can be positive or negative. Because it is defined as a change in velocity or speed, it cannot be zero. This explains why there should be some acceleration motion.
Formula = displacement/timeFormula= velocity/time