Velocity vs Average Velocity
Velocity is a very important property discussed under the field of mechanics in physics. Velocity of an object describes how fast the object is moving and the direction of its movement. The average velocity describes the overall effective velocity of a motion. Both of these concepts are fairly basic and very important in almost every branch of physics. In this article, we are going to discuss what velocity and average velocity are, the definitions of velocity and average velocity, their similarities and finally the difference between velocity and average velocity.
Velocity is a physical quantity of a body. The instantaneous velocity can be given as the instantaneous speed of the object with the direction the object is moving at that moment. In Newtonian mechanics, the velocity is defined as the rate of change of displacement. Both velocity and displacement are vectors. They have a quantitative value and a direction. The quantitative value of the velocity alone is called the modulus of velocity. This is equal to the speed of the object. The average velocity of an object is the difference between final and the initial velocity (separately in three dimensions) divided by the total time. The velocity of an object is directly related to the kinetic energy of the object. In classical mechanics, the kinetic energy of an object is half times the mass multiplied by velocity squared (Ek=½ mv2). The theory of relativity suggests a more advanced version, which is not discussed here. The theory of relativity also suggests that the observed mass of an object increases when the velocity of the object is increased. The velocity of an object is dependent only on the changes of space time coordinate of the object.
Average velocity is the average of the instantaneous velocities over a time period. Since this is hard to obtain, a more easy method is used to calculate the average velocity. The average velocity of a motion is the total distance traveled by the object divided by the time taken for the journey. If the path of the object is a straight line, a vector for the average velocity can be obtained easily. Another method for obtaining the average velocity is to integrate the instantaneous velocity with respect to time for the journey. This yields the distance traveled by the object. By dividing this quantity by the time taken for the journey, the average velocity can be calculated.
What is the difference between Velocity and Average Velocity?
• Velocity of an object is an instantaneous property for a given motion whereas the average velocity always corresponds to the overall motion between two points.
• An object can have a value for velocity when the displacement is zero, however, the average velocity of any object with zero displacement is also zero.
• The vector of velocity lies in the instantaneous direction of the object. The direction of average velocity depends on the starting point and the displacement of the object. Always, the average velocity vector is parallel to the displacement vector.