Question

If a displacement-time graph of an object is a straight line parallel to the time axis, the object is
A. stationary
B. moving away from the reference point
C. moving towards the reference point
D. moving with an infinite velocity

Answer 1

Hint: Ordinate of the displacement-time graph of the given object represents displacement and abscissa represents the time period of the object. Using the displacement-time graph, we can evaluate the displacement and velocity of the given object any time instant.

Complete step by step answer:
We are given the displacement-time graph of an object which is a straight line parallel to the axis of time and we are asked to define the position of the object.
Displacement-time graph of an object shows the variation of displacement of that body at a various time instant. If we consider the slope of the displacement-time graph, it will be equal to the velocity of the object.
It is given that the displacement-time graph of the given object is a straight line parallel to the time axis which means the value of displacement is not changing with the time that means the slope of the displacement-time graph is zero. In other words, we can say that the velocity of the given object will be zero. We also know that the velocity of an object is zero when it is in a stationary position.
Therefore, based on the above explanation we can say that if the displacement-time graph of the given object is a straight line parallel to the time axis, the object is stationary

So, the correct answer is “Option A”.

Note:
With the help of the displacement-time graph, we can calculate the average velocity of the given object, which will be equal to the ratio of average displacement to the average time period.
 we can also say that the velocity of the given object will be zero.