When the elevator is stationary, it begins to rise at a constant acceleration of A1 for 2 seconds, then decelerates at a constant acceleration of A2, and stops after 3 seconds. It is known that the elevator's rising height is 15 m. The maximum speed and the accelerations of A1 and A2 in the process of movement are calculated

The maximum speed is V, the acceleration displacement S1, the deceleration displacement S2V = A1 * T1, v = A2 * t22a1 = 3a2, A2 = 2 / 3, a1s1 = 1 / 2 * A1 * T1 ^ 2, S1 = 1 / 2A1 * 4 = 2 * a1s2 = 1 / 2 * A2 * T2 ^ 2, S2 = 1 / 2A2 * 9 = 9 / 2 * A2, because A2 = 2 / 3 A1, S2 = 3 * a1s1 + S2 = 15m2 * a1 + 3 * A1 = 15m, A1 = 3M, A2 = 2m, v = 6m / s

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