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Ballistic trajectory

Storyboard

If an object is thrown or fired in a gravitational field, it undergoes two types of motion:• In the vertical axis, it moves due to the gravitational field, experiencing gravitational acceleration. For low-height trajectories, this acceleration can be considered constant.• In the horizontal axis, assuming air resistance is negligible, the object moves at a constant velocity because there is no force to accelerate or decelerate it.The result is what is known as a ballistic trajectory, which achieves its maximum range when thrown or fired at a 45-degree angle.

>Model

ID:(1446, 0)



Mechanisms

Concept


ID:(15404, 0)



Vision in the Middle Ages

Concept

During the Middle Ages, when observing the flight of a cannonball, a curve was drawn that showed a steep ascent followed by an almost vertical drop, as seen in the image:

However, by analyzing the equations of kinematics, it is known that the actual trajectory of the cannonball is very different. In fact, it is a parabola that is produced by the combination of vertical motion caused by gravity and constant horizontal motion.In other words, the time that the ball remains in the air is determined by its vertical motion, while the distance traveled in the horizontal direction is determined by its horizontal velocity.

ID:(13996, 0)



The ballistic trajectory

Concept

The ballistic trajectory typically follows an inverted parabola with a point of the maximum height reached ($y_{max}$) and ERROR:8431.1 with the maximum height time ($t_{max}$) and the time to impact ($t_{imp}$):

Note: Strictly speaking, the components should be estimated based on their values at ground level to accurately determine the parameters of the maximum height and impact point.

ID:(12536, 0)



Model

Concept


ID:(15407, 0)



Ballistic trajectory

Model

If an object is thrown or fired in a gravitational field, it undergoes two types of motion: • In the vertical axis, it moves due to the gravitational field, experiencing gravitational acceleration. For low-height trajectories, this acceleration can be considered constant. • In the horizontal axis, assuming air resistance is negligible, the object moves at a constant velocity because there is no force to accelerate or decelerate it. The result is what is known as a ballistic trajectory, which achieves its maximum range when thrown or fired at a 45-degree angle.

Variables

Symbol
Text
Variable
Value
Units
Calculate
MKS Value
MKS Units
$h$
h
Height at which to shoot
m
$v_{0x}$
v_0x
Initial horizontal speed
m/s
$v_0$
v_0
Initial Speed
m/s
$v_{0y}$
v_0y
Initial vertical speed
m/s
$x_{imp}$
x_imp
Maximum distance reached
m
$y_{max}$
y_max
Maximum height reached
m
$\phi$
phi
Maximum height reached
rad
$t_{max}$
t_max
Maximum height time
s
$x$
x
Position on the x-axis
m
$y$
y
Position on the y-axis
m
$t$
t
Time
s
$t_{imp}$
t_imp
Time to impact
s

Calculations


First, select the equation:   to ,  then, select the variable:   to 
x = v_0x * t y = h + v_0y * t - g * t ^2/2 v_0x = v_0 *cos( phi ) v_0y = v_0 *sin( phi ) t_imp = v_0 *sin( phi )*(1+sqrt(1+2* g * h /(v_0 ^2*sin( phi )^2)))/ g x_imp = v_0 ^2*sin( phi )*cos( phi )*(1+sqrt(1+2* g * h /( v_0 ^2*sin( phi )^2)))/ g t_max = v_0 *sin( phi )/ g y_max = h + v_0 ^2*sin( phi )^2/(2* g )hv_0xv_0v_0yx_impy_maxphit_maxxytt_imp

Symbol
Equation
Solved
Translated

Calculations

Symbol
Equation
Solved
Translated

 Variable   Given   Calculate   Target :   Equation   To be used
x = v_0x * t y = h + v_0y * t - g * t ^2/2 v_0x = v_0 *cos( phi ) v_0y = v_0 *sin( phi ) t_imp = v_0 *sin( phi )*(1+sqrt(1+2* g * h /(v_0 ^2*sin( phi )^2)))/ g x_imp = v_0 ^2*sin( phi )*cos( phi )*(1+sqrt(1+2* g * h /( v_0 ^2*sin( phi )^2)))/ g t_max = v_0 *sin( phi )/ g y_max = h + v_0 ^2*sin( phi )^2/(2* g )hv_0xv_0v_0yx_impy_maxphit_maxxytt_imp



Equations

The position ($s$) traveled with the constant velocity ($v_0$) with the starting position ($s_0$), the time ($t$), and the start Time ($t_0$) is

$ s = s_0 + v_0 ( t - t_0 )$



Therefore, if the motion starts at the origin ($s_0=0$) at the beginning of time ($t_0=0$), the motion is described by $x=s$ and $v_0=v_{0x}$.

$ x = v_{0x} t $

(ID 10930)

For the case where ERROR:5297,0 equals gravitational acceleration ($a_0=-g$), the vertical trajectory can be calculated using the equation for the position ($s$) with the starting position ($s_0$), the initial Speed ($v_0$), the time ($t$), and the start Time ($t_0$):

$ s = s_0 + v_0 ( t - t_0 )+\displaystyle\frac{1}{2} a_0 ( t - t_0 )^2$



In the scenario where the motion starts at the height at which to shoot ($h$) ($s_0=h$), the start Time ($t_0$) ($t_0=0$), and the initial vertical speed ($v_{0y}$) ($v_0=v_{0y}$) are given, the motion can be described by the formula:

$ y = h + v_{0y} t -\displaystyle\frac{1}{2} g t ^2$

(ID 10931)

To determine the impact time, we can use the equation of the position on the y-axis ($y$), which depends on the height at which to shoot ($h$), the initial vertical speed ($v_{0y}$), the gravitational Acceleration ($g$), and the time ($t$), where the height is zero:

$ y = h + v_{0y} t -\displaystyle\frac{1}{2} g t ^2$



This results in a time:

$t=\displaystyle\frac{ v_{y0} +\sqrt{ v_{0y} ^2 + 2 g h }}{g}$



With the initial Speed ($v_0$) and the maximum height reached ($\phi$):

$ v_{0y} = v_0 \sin \phi $



the time to impact ($t_{imp}$) is:

$ t_{imp} =\displaystyle\frac{ v_0 \sin \phi }{ g }\left(1+\sqrt{1+\displaystyle\frac{ 2 g h }{ v_0 ^2 \sin^2 \phi }}\right)$

(ID 10934)

Since the time to impact ($t_{imp}$) with the initial Speed ($v_0$), the maximum height reached ($\phi$), the gravitational Acceleration ($g$), and the height at which to shoot ($h$) is

$ t_{imp} =\displaystyle\frac{ v_0 \sin \phi }{ g }\left(1+\sqrt{1+\displaystyle\frac{ 2 g h }{ v_0 ^2 \sin^2 \phi }}\right)$



then the position on the x-axis ($x$) with the initial horizontal speed ($v_{0x}$) and the time ($t$)

$ x = v_{0x} t $



and the initial horizontal speed ($v_{0x}$) with the initial Speed ($v_0$) and the maximum height reached ($\phi$)

$ v_{0x} = v_0 \cos \phi $



thus, we have

$ x_{imp} =\displaystyle\frac{ v_0 ^2\sin \phi \cos \phi }{ g }\left(1 + \sqrt{1 + \displaystyle\frac{2 g h }{ v_0 ^2\sin^2 \phi }}\right)$

(ID 10935)

The maximum height time ($t_{max}$) is reached when the position on the y-axis ($y$) reaches a maximum value. This height can be calculated with the height at which to shoot ($h$), the initial vertical speed ($v_{0y}$), the gravitational Acceleration ($g$), and the time ($t$),

$ y = h + v_{0y} t -\displaystyle\frac{1}{2} g t ^2$



whose derivative with respect to time is zero at the maximum, implying:

$\displaystyle\frac{dy}{dt}=v_{0,y}-gt=0$



Therefore, with the expression for the initial Speed ($v_0$),

$ v_{0y} = v_0 \sin \phi $



we have that

$ t_{max} =\displaystyle\frac{ v_0 }{ g }\sin \phi $

(ID 10936)

The maximum height reached ($y_{max}$) is reached in a maximum height time ($t_{max}$) with the maximum height reached ($\phi$), the constant velocity ($v_0$), and the gravitational Acceleration ($g$),

$ t_{max} =\displaystyle\frac{ v_0 }{ g }\sin \phi $



from which we can determine the position on the y-axis ($y$) with the height at which to shoot ($h$), the initial vertical speed ($v_{0y}$), and the time ($t$) using the equation

$ y = h + v_{0y} t -\displaystyle\frac{1}{2} g t ^2$



Thus, with the initial vertical speed ($v_{0y}$),

$ v_{0y} = v_0 \sin \phi $



at the maximum height reached ($y_{max}$), it is

$ y_{max} = h + \displaystyle\frac{ v_0 ^2}{2 g }\sin^2 \phi $

(ID 10937)


Examples


(ID 15404)

During the Middle Ages, when observing the flight of a cannonball, a curve was drawn that showed a steep ascent followed by an almost vertical drop, as seen in the image:

However, by analyzing the equations of kinematics, it is known that the actual trajectory of the cannonball is very different. In fact, it is a parabola that is produced by the combination of vertical motion caused by gravity and constant horizontal motion.In other words, the time that the ball remains in the air is determined by its vertical motion, while the distance traveled in the horizontal direction is determined by its horizontal velocity.

(ID 13996)

The ballistic trajectory typically follows an inverted parabola with a point of the maximum height reached ($y_{max}$) and ERROR:8431.1 with the maximum height time ($t_{max}$) and the time to impact ($t_{imp}$):

Note: Strictly speaking, the components should be estimated based on their values at ground level to accurately determine the parameters of the maximum height and impact point.

(ID 12536)


(ID 15407)


ID:(1446, 0)