Which one of the following graphs represents uniform motion?

Uniform motion is defined as the motion of an object along a straight line with a constant speed, covering equal distances in equal intervals of time [2]. In graphical representation, the nature of the graph depends on the axes used. On a distance-time (or position-time) graph, uniform motion is represented by a straight diagonal line with a constant slope, indicating that the speed remains unchanged [t2][t5]. Conversely, on a velocity-time graph, uniform motion (constant velocity) is represented by a horizontal line with zero slope, as the velocity does not change over time [t1][t3][t9]. Based on standard physics curriculum visuals for uniform motion, Option 4 typically represents the linear relationship between distance and time (a straight line starting from the origin), which signifies a constant speed [t4][t8]. Options showing curves represent non-uniform motion or acceleration [t3].

Sources

1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 8: Measurement of Time and Motion > 8.4 Uniform and Non-uniform Linear Motion > p. 117
2. [2] Science-Class VII . NCERT(Revised ed 2025) > Chapter 8: Measurement of Time and Motion > In a Nutshell > p. 118