Test: Motion- 2 - Class 9 MCQ

The equations of motion are applicable only when the body moves with uniform acceleration. A body under constant acceleration is uniformly accelerated motion.

• Displacement is the shortest straight line distance between the initial and final position. This means that there doesn't exist any other path which is shorter than it.
• If the object travels with that shortest straight-line path then the magnitude of distance and displacement would be the same.
• If the object doesn't do so and travels with any other paths then as the other path is not the shortest path, so it will be larger than that of displacement. So if the object travels with this path then the magnitude of displacement will be smaller than the distance.

Thus, the magnitude of displacement may be equal to or smaller than that of distance.

v = u + at
or = 2m/s²
s = ut + 
= 100 m

It is horizontal so, angle is zero and also acceleration is zero. Hence constant velocity.

In figure A, we can see that the object continues to remain at a fixed place while the time keeps running. So, the object is at rest, because the object does not change its position with time.

"Displacement" is the quantity that is measured by the area occupied under the velocity-time graph. Moving something or someone from its place or position is called displacement.

The slope of a velocity-time graph represents the acceleration of the object. So, the value of the slope at a particular time represents the acceleration of the object at that instant.

Assertion (A): Incorrect. On a velocity-time graph, uniform acceleration is represented by a straight line, not a parabolic trajectory. A parabolic trajectory is seen on a position-time graph for uniformly accelerated motion.
Reason (R): Incorrect. The distance-time graph for uniform acceleration is not a straight line but a curve. A straight-line distance-time graph indicates uniform velocity, not acceleration.
Explanation: Both the Assertion and Reason are false. The Assertion is incorrect because uniform acceleration on a velocity-time graph is a straight line. The Reason is incorrect as well because uniform acceleration produces a curved distance-time graph.