Uniform motion is defined as the motion of an object in which the object travels with a constant speed along a straight line. We say the object is moving with a constant speed if it covers equal distances in equal intervals of time.

In a uniform motion, the instantaneous velocity at any time over the entire trip is the same as the average speed. If an object starts from an initial position x0 and travels at a constant velocity, v, then its position, x, at any time, t, is given by

X = X₀ + vt

Then, the displacement at any time t, becomes

d = X - X₀ = vt

Key Terms

• Uniform motion, motion at a steady speed in a straight line