Answer:38.675 m/s
Explanation:
[tex]\theta =25^{\circ}[/tex]
t=4.2 s
[tex]R_x=105m[/tex]
Solving in x direction
[tex]R_x=ut+\frac{1}{2}\left ( 0\right )t^2[/tex]
[tex]105=ucos25\times 4.2[/tex]
ucos25=25
u=27.584 m/s
Initial velocity in vertical direction usin25
Let h be the height of Rooftop
[tex]h=\left ( -usin25\right )4.2+\frac{1}{2} \left ( 9.8\right )\left ( 4.2\right )^2[/tex]
h=37.47 m
Therefore final vertical velocity is [tex]v_{vf}^2-\left ( usin25\right )^2=2\times 9.81\times 37.47[/tex]
[tex]v_{vf}[/tex]=29.51 m/s
Final Resultant velocity
[tex]V_{final}=\sqrt{29.51^2+24.99^2}[/tex]
[tex]V_{final}=38.675 m/s[/tex]
