The first thing we have to do for this case is write the kinematic equationsto
vf = a * t + vo
rf = a * (t ^ 2/2) + vo * t + ro
Then, for the bolt we have:
100% of your fall:
97 = g * (t ^ 2/2)
clearing t
t = root (2 * ((97) / (9.8)))
t = 4.449260429
89% of your fall:
0.89*97 = g * (t ^ 2/2)
clearing t
t = root (2 * ((0.89 * 97) / (9.8)))
t = 4.197423894
11% of your fall
t = 4.449260429-4.197423894
t = 0.252
To know the speed when the last 11% of your fall begins, you must first know how long it took you to get there:
86.33 = g * (t ^ 2/2)
Determining t:
t = root (2 * ((86.33) / (9.8))) =
4.19742389 s
Then, your speed will be:
vf = (9.8) * (4.19742389) = 41.135 m / s
Speed just before reaching the ground:
The time will be:
t = 0.252 +
4.197423894 =
4.449423894 s
The speed is
vf = (9.8) * (4.449423894) =
43.603 m / s
answer
(a) t = 0.252 s
(b) 41,135 m / s
(c) 43.603 m / s