A force F varies with displacement d as in the graph: F=0 from d=0 to 3 m, F=2 N from 3 to 7 m, and then decreases linearly to zero at d=12 m. Find work done in 12 m.

Question

G1 Physics · Accepted Answer

Step 1 — Principle: For a position-dependent force, calculate work by integrating force along displacement: W = ∫F dx. Step 2 — Working: Work equals the area under F–d graph: rectangle 2(7-3)=8 J; triangle ½(12-7)×2=5 J. Step 3 — Working: Total W=13 J. Correct answer: C — 13 J.