Uniform motion is motion where the velocity does not change with time, that is, the velocity is constant.
Knowing that the average speed of a mobile can be given by:
v = Δs
Δt
Where:
Δs = s – s0 , is the space variation, measured in meters (m)
Δt = t – t0, is the time variation, measured in seconds (s)
Making the initial time equal to zero (t0 = 0) we have:
v = s – s0
t
Isolating the final space(s) in the equation, we have:
s = s0 + vtv ≠ 0 (time function of MU space)
We can see that space is a function of time. s = f
A 1st degree function is graphically represented by a straight line, in the Cartesian coordinate system, in relation to the time axis.
For v > 0 the function is increasing, so the graph of the function can be:
MU plot for v = cte. >0
We note that the graph of the function is an increasing line, therefore, the movement is progressive, that is, the mobile moves in the same direction and sense of the orientation of the trajectory.
For v < 0 the function is decreasing, and the graphical representation of the function is:
Don’t stop now… There’s more after the publicity 😉
Graph of MU, for v = cte. < 0
In this case, the velocity is less than zero (v < 0), the movement is retrograde, that is, the mobile moves in the opposite direction to the orientation of the trajectory.
speed graphs
Since the average speed is constant, the graphs can be:
1 – For v > 0:
v > 0 – Progressive Movement
Note that the velocity graph is a line parallel to the time axis, so v = f
v < 0 - Retrograde Motion
Note: The graphs do not determine the trajectory, they only represent the functions of the movement.
Since acceleration is zero in uniform motion (a=0), the acceleration graph is a straight line that coincides with the time axis.
MU acceleration graph
* cte = constant
See more!!!
Graphs of Uniformly Varied Motion
By Kleber Cavalcante
Graduated in Physics
Team
Mechanics – Physics –