Environmental Engineering Reference
In-Depth Information
22
v
cos
2
α
2
0
(
)
f
=
tg
αβ
+
tg
[4.19]
g
Figure 4.7.
Flight trajectory (parabola)
These elements are very useful in the study of practical cases, especially when
designing protective structures. The velocities are expressed in the following way:
vv
=
cos
α
vv
=
sin
α
−
t
[4.20]
x
0
y
0
The beginning of flight is:
t
=
0
v
=
v
δαβ
= +
[4.21]
0
0
The end of flight is:
s
cos
β
)
2
22
(
t
=
v
=
v
cos
α
+
v
sin
α
−
gt
[4.22]
1
1
0
0
1
v
cos
α
0
⎛
⎞
v
tg
v
o
1
x
y
δ
=−−
90
⎜
β
arc
⎟
[4.23]
1
⎜
⎟
⎝
1
⎠
