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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): \(s_1 = \tfrac{1}{2}(0+20)(5) = 50\ \text{m}\).
Phase 2 (constant): \(s_2 = 20 \times 10 = 200\ \text{m}\).
Phase 3 (brake): \(s_3 = \tfrac{1}{2}(20+0)(6) = 60\ \text{m}\).
Total distance \(= 50 + 200 + 60 = 310\ \text{m}\).
