Which of the following is true for displacement ?
(a) It cannot be zero.
(b) Its magnitude is greater than the distance travelled by the object.

Explanation

To determine which of the statements regarding displacement is true, we will analyze both options provided in the question.

### Step 1: Understand the definition of displacement
Displacement is defined as the shortest distance between the initial and final positions of an object, along with the direction. It is a vector quantity, meaning it has both magnitude and direction.

### Step 2: Analyze Option A
Option A states that "displacement cannot be zero." This statement is false. Displacement can indeed be zero. For example, if an object starts from point A, moves in any direction, and then returns back to point A, the initial and final positions are the same. Therefore, the shortest distance between these two points (A to A) is zero.

**Conclusion for Option A:** Displacement can be zero.

### Step 3: Analyze Option B
Option B states that "the magnitude of displacement is greater than the distance travelled by the object." This statement is also false. The distance travelled by an object is the total path length covered, while displacement is the shortest distance between the starting and ending points.

For instance, if an object moves from point A to point B (10 meters) and then from point B to point C (10 meters), the total distance travelled is 20 meters. However, if the object returns to point A, the displacement is the shortest distance from A to C, which could be less than the total distance travelled.

**Conclusion for Option B:** The magnitude of displacement can be less than or equal to the distance travelled.

### Final Conclusion
Both options A and B are false. Displacement can be zero, and its magnitude is not always greater than the distance travelled.

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