Acceleration And Velocity Problem

AI Thread Summary
The discussion centers on confusion regarding the equations of motion, specifically when initial velocity (u) is zero. The equations v = u + at and S = ut + 1/2at^2 are highlighted, with a particular focus on the derived relationships when u equals zero. The user notes a discrepancy between instantaneous velocity (v = at) and average velocity (V = S/t). The key point is that instantaneous velocity is calculated at a specific moment, while average velocity considers total distance over total time. Understanding this distinction clarifies the apparent contradiction in the equations.
varunKanpur
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I am having a problem in understanding the equation of motions.

The equation of motion are
v=u+at
S=ut +1/2at^2

Velocity= distance/ time=d/t

The problem is that if u=0 then
V=at. Equation.1

S=1/2at^2
V=S/t=1/2at not equal to equation 1

What am I doing wrong??
Thanx
 
Physics news on Phys.org
v = u + a*t gives INSTANTANEOUS velocity at time t.

But, if you use v = s/t you get the AVERAGE velocity.
 

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