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?12?1. A car starts from rest and with constant acceleration achieves a velocity of 15 m>s when it travels a distance of 200 m. Determine the acceleration of the car and the time required.
Kinematics: v0 = 0, v = 15 m>s, s0 = 0, and s = 200 m. + A:B v2 = v0 2 + 2ac(s  s0) 152 = 02 + 2ac(200  0) ac = 0.5625 m>s2 + A:B v = v0 + act 15 = 0 + 0.5625t t = ¡¦(»ý·«)
26.7 s Ans. Ans.
12?2. A train starts from rest at a station and travels with a constant acceleration of 1 m>s2. Determine the velocity of the train when t = 30 s and the distance traveled during this time.
Kinematics: ac = 1 m>s2, v0 = 0, s0 = 0, and t = 30 s. + A:B + A:B v = v0 + act = 0 + 1
