RRB Group D 27 Nov 2025 Shift 1 Solved Paper

Concept:Work done can be positive, negative, or zero depending on the angle between force and displacement.Explanation:Work done is given by $W = F \cdot d \cdot \cos \theta$, where $F$ is force, $d$ is displacement, and $\theta$ is the angle between them.If $\theta < 90^\circ$, $\cos \theta > 0$, so work is positive (force and displacement are in the same direction).If $\theta > 90^\circ$, $\cos \theta < 0$, so work is negative (force and displacement are in opposite directions).If $\theta = 90^\circ$, $\cos \theta = 0$, so work is zero (force is perpendicular to displacement).Work also depends on the magnitudes of force and displacement; it is not independent of them.Therefore, only the statement "Work done can be positive or negative depending on the direction of force" is correct.Answer:Option B.