A jetliner touches down

Question

A jetliner touches down at 220 km/h and comes to a halt(stop) 29 s later. What is the shortest runway

on which this aircraft can land?

Answer 1

V_initial = 220 km/hr. Convert to m/s: (220 km/hr)(1000m/1km)(1hr/3600s) = 61.11 m/s

Calculate maximum deceleration: a = Δv/Δt = (v_final - v_initial)/Δt = (0 - 61.11)/29 = -2.107 m/s²

Calculate distance using the kinematic equation x = v_initialt + 1/2at²

x = v_initialt + 1/2at² = (61.11)(29) + (1/2)(-2.107)(29²) = 1772.2 - 886.11 = 886 meters