The aircraft takes off along the horizontal runway at an acceleration of 10m / s from standstill. What is the initial speed in the third second? What is the displacement in the third second? What is the average speed in the third second? What is the average speed in the first three seconds?

The aircraft takes off along the horizontal runway at an acceleration of 10m / s from standstill. What is the initial speed in the third second? What is the displacement in the third second? What is the average speed in the third second? What is the average speed in the first three seconds?

1） V3=at3= 10*3=30m/s
2) Displacement in the first 2 seconds: x2 = (1 / 2) a (T2) ^ 2 = 0.5 * 10 * 2 ^ 2 = 20m
Displacement in the first 3 seconds: X3 = (1 / 2) a (T3) ^ 2 = 0.5 * 10 * 3 ^ 2 = 45m
Displacement in 3S: △ X3 = x3-x2 = 25m
3) Average speed in the third second: v = △ X3 / 1 = 25m / S (only 1 second in the third second)
4) Average velocity in the first three seconds: vping = X3 / T3 = 45 / 3 = 15m / S