Difference between Speed and Velocity: Complete Details

One of the most fascinating concepts in physics is the difference between velocity and speed. Also, a frequently asked question in board examinations and competitive entrance exams like JEE and NEET is what the difference is between speed and velocity. In daily communication, the terms “speed” and “velocity” have similar meanings to us. However, the concepts in “physics” and “mathematics” are totally different from one another. 

While velocity refers to the rate and direction of an object’s movement, speed is the time rate at which an object moves along a path. As stated otherwise, velocity is a vector value, and speed is a scalar value. 

Below is a detailed explanation of speed and velocity, with examples.

Also Read: What is the Difference Between Standard Deviation and Standard Error?

What is Speed?

Speed is the amount of distance travelled in a given amount of time. For instance, let’s say you and your travel partner start from the same starting point and need to get to a destination. While your friend rides a bicycle, you are walking. Despite travelling the same distance, your friend will arrive at the destination before you do. The same distance was travelled by both of you in varying amounts of time. This indicates that your companion is moving faster than you are. 

When talking about speed, the points mentioned below need to be kept in mind.

• Speed of a body is defined as the distance covered by the body in per unit time.
• Determines how fast an object is moving.
• It is the speed at which distance changes in relation to time.
• The metre per second (ms-1) is its SI unit.
• It is a scalar quantity i.e., it has only magnitude.
• It is positive and non-zero number.

Types of Speed

The various speed types are listed below:

1. Average speed: It is defined as the body’s overall distance travelled to its total time.
2. Relative speed: The term refers to the speed that is determined between two bodies in relation to one another.
3. Instantaneous speed: This refers to a body’s speed at any given moment.
4. Tangential speed: The body’s speed when travelling in a circle is referred to as this.
5. Rotational speed: It is defined as a body’s number of rotations per unit of time.

Example

Suppose a truck travels a distance of 500 kilometers in 7 hours. Formula for calculating the speed: Speed= Distance / Time

Speed= 500 / 7 = 71.42 km/h

Therefore, the truck’s speed is 71.42 km/h. This value tells the rate at which the truck is covering the distance, regardless of the direction.

What is Velocity?

The rate at which an object’s position changes in relation to time is called its velocity. Velocity possesses both direction and magnitude. As a result, speed is a scalar quantity, whereas velocity is a vector quantity. 

When talking about velocity, the points mentioned below need to be kept in mind.

• The distance travelled by a body in a given amount of time is known as its velocity.
• The direction and speed of an object’s motion are both described by its velocity.
• It is the speed at which displacement varies over time.
• The metre per second (ms-1) is its SI unit.
• It has both magnitude and direction, making it a vector quantity.  
• It may be zero, negative, or positive.

Types of Velocity

The types of velocity are:

1. Constant Velocity: A velocity that moves in a straight line without changing in magnitude or direction is referred to as constant velocity.
2. Changing Velocity: A velocity is said to be changing if it modifies either its direction or its magnitude, or both.
3. Instantaneous velocity: It is the term used to describe a body’s velocity at any given moment.
4. Terminal Velocity: The body’s velocity that results from a fall caused by gravity is referred to as the terminal velocity.
5. Relative Velocity: Relative velocity is the speed determined by a single coordinate system between two objects.

Example

Assume a person walks for 3 hours from point A to point B, which is 6 kilometres west. Formula for Velocity: Velocity = Displacement / time.

Velocity = 6 km (west) / 3 hours = 2 km/h (west)

Therefore, the person’s velocity is 2 km/h west. This value represents both speed and direction 

of the person.

Also Read: What is the Difference Between Permanent Residency and Citizenship? Complete Details

Difference between Speed and Velocity

For students and candidates preparing for JEE or related exams, it is important to understand the difference between speed and velocity. Below is the table mentioned to help you understand it.

Characterization	Speed	Velocity
Definition	Speed is the ratio of distance to time	Velocity is the ratio of displacement to time
Formula	Speed = Distance / Time	Velocity = Displacement / Time
Quantity	Scalar quantity	Vector quantity
Direction	It does not have direction	It has direction
Magnitude	Can be positive and non-zero	Can be positive, negative, or zero
Units	Speed is typically expressed in units such as m/s, km/h, mph	Velocity share the same units as speed but include a direction component (e.g. m/s east)
Example	A person is riding a bicycle at a speed of 20 km/s	A person is riding a bicycle with a speed of 20 km/s towards the east

Similarities between Speed and Velocity

They both are way different but they still have a few similarities. The following list highlights similarities between velocity and speed:

• A metre per second is the SI unit for both velocity and speed (ms-1).
• [LT-1] is the dimension formula for velocity and speed.
• Velocity and speed both have magnitudes.

Related Posts

Difference Between Feet and Square Feet	What is the Difference Between Gross Weight and Net Weight?
Difference Between Longitudinal and Transverse Wave	What is the Difference Between H Beam and I Beam?
What is the Difference Between Capacitor and Condenser?	What is the Difference Between Prime and Composite Numbers

FAQs

This was all about the “Difference between Speed and Velocity”.  For more such informative blogs, check out our Study Material Section, you can learn more about us by visiting our  Indian exams page.