Answer:
47.43 m/s
Step-by-step explanation:
Given that,
Final speed of a plane, v = 0
Distance, d = 180 m
Acceleration of the plane, a = -6.25 m/s² (deceleration )
We need to find the plane's velocity. Let it was u. So, using the third equation of kinematics as :

So, the plane's velocity when it first touched the landing strip is 47.43 m/s.