Answer:
20.425 m
Step-by-step explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²
[tex]s=ut+\frac{1}{2}at^2\\\Rightarrow u=\frac{s-\frac{1}{2}at^2}{t}\\\Rightarrow u=\frac{1.2-\frac{1}{2}\times 9.81\times 0.125^2}{0.125}\\\Rightarrow u=8.98\ m/s[/tex]
Now this will the final velocity when it reaches the top of the window
[tex]v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{8.98^2-0^2}{2\times 9.81}\\\Rightarrow s=4.11\ m[/tex]
[tex]v=u+at\\\Rightarrow v=8.98+9.81\times 0.125\\\Rightarrow v=10.21\ m/s[/tex]
If the upward flight is an exact reverse of the downward flight then the time taken while going down will be 1 second and going up will be 1 second.
[tex]s=ut+\frac{1}{2}at^2\\\Rightarrow s=10.21\times 1+\frac{1}{2}\times 9.81\times 1^2\\\Rightarrow s=15.115\ m[/tex]
Hence total height of the building is 4.11+1.2+15.115 = 20.425 m
