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A car starts from rest and accelerates uniformly to 20 m s⁻¹ in 5 seconds. It then travels at 20 m s⁻¹ for 10 seconds and finally applies the brake (with uniform acceleration) to stop in 6 seconds. Find the total distance travelled.
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Phase 1 (speed up): s 1 = 1 2 (0+20)(5) = 50 m .
Phase 2 (constant): s 2 = 20 × 10 = 200 m .
Phase 3 (brake): s 3 = 1 2 (20+0)(6) = 60 m .
Total distance = 50 + 200 + 60 = 310 m .
| Phase | Distance |
|---|---|
| Speeding up (5 s) | 50 m |
| Constant speed (10 s) | 200 m |
| Braking (6 s) | 60 m |
| Total | 310 m |
