An airplane touches down at a speed of 100m/s. It travels 1000 metres along the runway
while deceleration at a constant rate before coming to rest. How long did it take the airplane to come to rest on the runway?
Xi=0m/s Xf=1000m Vix=100m/s
The Attempt at a Solution
Why is the answer 20 s? and why does this formula fail?