Question

Самолёт прошёл взлётную полосу за 20 с и в момент отрыва от земли имел скорость 120 м/с.С каким ускорением он двигался по взлётной полосе и какова её длина?

Answer 1

Дано:

$t=20\\ v_{0}=0 \\v=120$

 

Решение:

$a=\frac{v-v_{0}}{t}=\frac{120-0}{20}=6\\ S=v_{0}t+\frac{at^2}{2}=0*20+\frac{6*20^2}{2}=1200$

 

Ответ: a=6 м/с^2; S=1200 м

Answer 2

Calculation of Acceleration and Length of the Runway

To calculate the acceleration and length of the runway, we can use the equations of motion and the given information.

Let's denote the acceleration as a and the length of the runway as d.

Given: - Time taken to cover the runway, t = 20 s - Velocity at takeoff, v = 120 m/s

Using the equation of motion v = u + at, where u is the initial velocity, we can find the acceleration a:

v = u + at

Substituting the values: 120 m/s = 0 + a * 20 s

Simplifying the equation: a = 120 m/s / 20 s = 6 m/s^2

Therefore, the acceleration of the airplane on the runway is 6 m/s^2.

To find the length of the runway, we can use the equation of motion s = ut + (1/2)at^2, where s is the distance covered.

Since the initial velocity u is 0 (the airplane starts from rest), the equation becomes: s = (1/2)at^2

Substituting the values: s = (1/2) * 6 m/s^2 * (20 s)^2

Simplifying the equation: s = 6 m/s^2 * 400 s^2 = 2400 m

Therefore, the length of the runway is 2400 meters.

Please note that these calculations assume constant acceleration and neglect other factors such as air resistance.