Question

Which of the following is not true for displacement?( this question has multiple correct answers)
A. it cannot be zero
B. Its magnitude is greater than the distance travelled by the object.
C. it can be zero
D. its magnitude is less than the distance travelled by the object.

Answer 1

Hint: Displacement is defined as the shortest possible distance covered by any object. It is a vector quantity; it has both magnitude and direction. Displacement depends on the position of the object. The magnitude of the displacement is given as the difference in the position of the object.

Formula used: $d=f-i$

Complete step by step answer:
Displacement is given mathematically as, $d=f-i$, where, $f$ and $i$ are the final and the initial positions respectively.
If an object comes to the same position then the displacement is zero.
Then clearly, option C is true.
Since displacement by definition is the shortest distance covered, then it must be less than the distance covered.
Then clearly option D is true.
But here the question is asking what is not true or what is false about displacement. Then clearly, option A and B is the answer.

So, the correct answers are “Option A and B”.

Note: Often students confuse between distance and displacement. It is important to understand that the two are different in the following ways. Distance is the total path covered, whereas displacement is the shortest path taken by an object. Distance is always positive and it is a scalar quantity, whereas displacement is a vector and it can be positive, negative or zero depending on the direction of the motion. The rate of change of distance is given as speed, whereas the rate of change of displacement is given as velocity. Since displacement is a vector, velocity is also a vector. Similarly, since distance is a scalar, speed is also a scalar.