Final answer:
The question involves calculating the deceleration of a WW2 airman who survives a fall and the reduction in velocity of a landing airplane. The deceleration of the airman can be computed using kinematics equations, while the decrease in plane's speed involves understanding negative acceleration or deceleration over time.
Step-by-step explanation:
The question relates to the deceleration experienced by airmen during World War II who survived falls from great heights, as well as the analysis of an airplane's speed reduction upon landing. To calculate the deceleration of a falling airman who impacts the ground at 54 m/s and is stopped by trees and snow over a distance of 3 meters, we use the formula a = Δv / Δt, where Δv is the change in velocity and Δt is the change in time. However, since we don't have the time, we can use the formula v^2 = u^2 + 2as, where v is the final velocity, u is the initial velocity, a is the acceleration (or deceleration in this case), and s is the distance over which deceleration occurs. Deceleration can be calculated by re-arranging this formula to a = (v^2 - u^2) / (2s). Given the final velocity v is 0 m/s (since the airman comes to a stop), the initial velocity u is 54 m/s, and s is 3.0 m, the deceleration a can be determined.
For the airplane landing, we have an initial velocity of 70.0 m/s which reduces to a final velocity of 10.0 m/s over a duration of 40.0 s. The final velocity can be found by using the formula v = u + at, where u is the initial velocity, a is acceleration (negative for deceleration), and t is the time period over which the velocity changes.