When a plane takes off and taxis, it starts to make uniform acceleration linear motion from static state, with the acceleration of 4m / S2. When the taxiing speed of the plane reaches 85m / s, it leaves the ground and takes off. If the plane suddenly receives the command from the command tower to stop taking off when it reaches the take-off speed, the pilot immediately stops the plane, and the plane makes uniform deceleration linear motion, with the acceleration of 5m / S2 How long does it take for a plane to reach maximum speed from take-off? (2) How long does the plane take from take-off to stop?

When a plane takes off and taxis, it starts to make uniform acceleration linear motion from static state, with the acceleration of 4m / S2. When the taxiing speed of the plane reaches 85m / s, it leaves the ground and takes off. If the plane suddenly receives the command from the command tower to stop taking off when it reaches the take-off speed, the pilot immediately stops the plane, and the plane makes uniform deceleration linear motion, with the acceleration of 5m / S2 How long does it take for a plane to reach maximum speed from take-off? (2) How long does the plane take from take-off to stop?

(1) According to a = V − v0t & nbsp;, the aircraft take-off time: T1 = va1 = 854s = 21.25s (2) aircraft deceleration time: T2 = 0 − va2 = − 85 − 5S = 17s, aircraft total time: T = T1 + T2 = 21.25s + 17s = 38.25 & nbsp; s answer: (1) this aircraft takes off from