Question

Upon reaching a velocity of 100fps, the pilot of the airplane decides to abort the take off and applies brakes and stops the airplane in 1000ft. What is the airplane’s deceleration? in absolute value

Answer 1

Answer:

$5ft/s^2$

Explanation:

We will use the formula for accelerated motion $v_f^2=v_i^2+2ad$, which for acceleration it means:

$a=\frac{v_f^2-v_i^2}{2d}$

In our case our initial velocity is $v_i=100ft/s$ and our final velocity is $v_f=0ft/s$ since it comes to rest, this process while traveling a distance $d=1000ft$, so we have:

$a=\frac{v_f^2-v_i^2}{2d}=\frac{(0m/s)^2-(100ft/s)^2}{2(1000ft)}=-5ft/s^2$

Which in absolute value means a deceleration of $5ft/s^2$