v y {\displaystyle v_{y}}
Δ y = v y t + 1 2 a t 2 {\displaystyle \Delta y=v_{y}t+{\frac {1}{2}}at^{2}}
− 88 = v y t + 1 2 ( − 0.05 ) t 2 {\displaystyle -88=v_{y}t+{\frac {1}{2}}(-0.05)t^{2}}
− 0.025 t 2 + v y t + 88 = 0 {\displaystyle -0.025t^{2}+v_{y}t+88=0}
t 1 = 20 v y + 4 25 v y 2 + 220 {\displaystyle t_{1}=20v_{y}+4{\sqrt {25v_{y}^{2}+220}}}
t 2 = 20 v y − 4 25 v y 2 + 220 {\displaystyle t_{2}=20v_{y}-4{\sqrt {25v_{y}^{2}+220}}}
1 3 < v y ≤ 7 6 {\displaystyle {\frac {1}{3}}<v_{y}\leq {}{\frac {7}{6}}}
