Motion is a term used to define the movement of an object or the body when it is changing its position with respect to its surroundings and time. The state of the body is determined using physical terms like velocity and speed.
The average velocity formula is a concept based on this, and to understand what it is, you must understand the basic terms first. These terminologies will help you understand better what average velocity is.
- Distance: This is the path covered by the body or the object with respect to the time without depending on a particular direction or path is called average velocity. Distance is considered a scalar quantity. The SI unit of distance is meter.
- Displacement: This can be defined as the shortest distance between two points or can be defined as the distance from the starting point to the finishing point with respect to time. Displacement has magnitude alongside the direction.
- Speed: The distance that is travelled by an object in unit time is considered as speed. It is measured in meter/second; the average speed is interpreted as the ratio of the total path covered during the journey to the time taken to complete the journey.
- Velocity: Velocity is the displacement of an object in unit time. Just like speed, velocity is also measured by meter/second. Considered to be a vector quantity, average velocity is explained as the ratio of net displacement of the body after completing the journey to the time taken to complete it.
Average Velocity- What Does It Mean?
In simple words, velocity and speed are what helps you figure out how fast an object or a body is moving and are interchangeable terms. However, in physics, it is a little bit more defined.
While during speed, with the object’s motion, the direction has no connection, but with velocity, the direction is always considered.
To understand average velocity here is a simple example: To cover twenty miles north and south, an individual takes 40 minutes ( ends up at the same place). The average speed would be 40 miles divided by 40 minutes, that is, 1 mile per minute.
Although, for average velocity, total displacement would be considered replacing distance. The average velocity will be calculated by dividing the total displacement by the time interval.
Relative Velocity- What Does It Mean?
Relative velocity could be defined as the measurement of the velocity between two bodies as found in a single coordinate system. In terms of classical and modern physics, relative velocity can be regarded as fundamental, where it deals with the relative motion of either two or more bodies.
While relative velocity does not depend on the chosen inertial reference frame in Newtonian mechanics. It does depend on spatial relativity.
The Formula Of Average Velocity
While calculating average velocity, the simplest formula one could use would be:
Average velocity = (change in position)/(change in time)
If a position function is given, s(t), giving the object position at time t, then to calculate average velocity, the formula would be:
Y-axis and X-axis represent the position of the body and time, respectively. The red curve represents the body’s movement with respect to time. The points of study here are P and Q.
- Another simple example would be: a car driver drives 40 kilometres within 5 minutes. Reversing, he drives 15km in 5 minutes. The average velocity would be:
V = D/t
V= (40-15)/ (5 5)
V= 25/10
V= 2.5 kilometer/minute
- A girl is known to walk 10km west in 3 hours and 5 km east in 2 hours. What do you think the total average velocity of the girl would be?
V=D/t
V= (10-5)/3 2
V= 5/5
V= 1 km/hr
What Is The Major Difference Between Average Speed And Average Velocity?
Average velocity is concerned with the displacement of the object. The magnitude can always differ from what the displacement of the actual path length is. This is where the average speed is used to define the rate of motion of a surface or path.
In the case of average speed, the total path covered is often divided by the time that has been taken. Average speed is a scalar quantity and is completely different from average velocity in this regard.
Average speed would never tell you about the motion direction; therefore, it is always considered to be positive.
Is there any similarity? Yes, both the terms are average of some length by the time taken. When considering the SI unit and other such standard units, it is the same for both the terms; even the formula is almost the same.
Can Average Velocity Be Zero?
If, for example, a car is travelling from starting point A and moving towards finishing point B and then returns to point A, there would be no total car displacement. In cases like this, the car speed can be calculated but the velocity cannot be.
But, if the same car moves from point A to point B and does not come back, there will be definite displacement. In simpler language, average velocity can also be considered the average speed but with a direction.
What Is Uniform And Non-Uniform Velocity?
When a body is travelling with a constant velocity in the same direction, it is said that it is travelling with uniform velocity.
Suppose the object or the body is travelling with a constant or a varying velocity, where either the speed and the direction are changing. In that case, the body is said to be travelling with non-uniform velocity. Speed is considered a scalar quantity, while average velocity is a vector one.
Conclusion
Many believe that average velocity and average speed are varied names for the same quantity. Still, it is crucial to understand that average speed depends on distance while your average velocity completely depends on the displacement.
Students who are studying velocity and speed for the first time can often get confused. But knowing them and understanding the concept is crucial to analyse and solve the graphical and theoretical questions.