The motion of an airplane is represented by velocity-time graph as shown below. The distance covered by airplane in the first 30.5 second is ____ km .
(A)9
(B)6
(C)3
(D)12✓ Correct
Answer: (D)
Solution
The distance covered equals the area under the velocity–time graph. From the graph, the velocity starts at 200 m/s at t=0, rises linearly to 400 m/s at t=2 s, and then stays constant at 400 m/s up to t=30.5 s.
Area of the initial trapezoidal segment (0 to 2 s):
2(200+400)×2=600 m
Area of the constant-velocity segment (2 s to 30.5 s):
400×(30.5−2)=400×28.5=11400 m
Total distance:
600+11400=12000 m=12 km
JEE Main · 2025 · 23 Jan 2025 · Shift 1 · Single correct option