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Projection calculator


*Input 2/3/4 values in any allowed fields
   
System of units:

Example: A projectile has an initial velocity of 12 m/s2 at an angle of 30°, it hits the ground at the end at an elevation of minus 1 m bellow the initial height, find trajection distance, and flight time.

Final elevation point at ground level
Initial velocity  (V0 ):
Trajectory angle  (θ0 ):
Trajectory distance  (S):
Horizontal velocity  (Vx ):
Vertical initial velocity  (V0y ):
Total travel time  (T):
Maximum height reached  (H):
Trajection values at selected locations during flight
Relative elevation  (ht):
Relative projection angle  (θt ):
Relative trajection distance (St):
Relative vertical velocity:(Vty ):
 
Relative trajectory velocity:  (Vt ):
 
Relative travel time  (Tt ):
 
Input limit:
Trajectory path equation:

Horizontal projection summary equations

Horizontal incline projection summary
Inclined motion draw

With no air resistance, winds or other disturbances the ideal horizontal velocity Vx is the same during the entire motion and resembles a parabola.

Earth gravity acceleration g is directed to the center of the earth and is equal to:

g = −9.80665 m/s2
Horizontal fall summary

Projection parabola path equation

Print projection parabola path equation
Horizontal fall summary - 1

Calculations table of different inputs

Calculations table of different inputs
* The values are presented for a complete flight cycle to reach the same altitude at the end of the motion, vertically it mean up to the highest point and back to the initial height.
**provide the relation between the x and y coordinates at any point of time in the motion of the projectile.
Horizontal fall summary table

Example 1 - path equation

Find the trajectile motion equation, and find the elevation of an object after passing a distance of 200 m in the x direction if it leaves a nozzle at a valocity of 50 m/s and at an angle of 35°.

In the x direction the acceleration of the object is zero therfore the velocity is constant and is equal to the initial velocity multiplyed by cosθ:

vx = v0 cosθ0

The displacement in the x direction described by constant speed is:

x=v_x  t=v_0  cos⁡〖θ_0 〗 t
(1)

the velocity in the y direction is the component of the initial velocity v0 in the y direction;

v_0y=v_0  sin⁡〖θ_0

The vertical dicplacement is calculated according to the free fall equations and replacing h by the value y.

h=v_0y  t-1/2 gt^2

y=v_0  sin⁡〖θ_0 〗  t-1/2 gt^2
(2)

To establish an equation that the values of y and x are bound together, we will substitute the value of t from equation (1) into equation (2) to get the equation:

y=v_0  sin⁡〖θ_0  x/(v_0  cos⁡〖θ_0 〗 )〗-1/2 g x^2/(〖v_0〗^2  cos^2⁡〖θ_0 〗 )

y=tan⁡〖θ_0  x-g/(2〖v_0〗^2  cos^2⁡〖θ_0 〗 )〗 x^2
(3)
Now we substitute the given values to equation (3) to find the elevation of the object after horizontal distance of 200m.
y=200 tan⁡35-9.8/(2∙50^2∙cos^2⁡35 ) 200^2=23.12m

Example 2 - angle of trajection

Find the angle that a catapult should fire an object at an initial velocity of 120 m/s2 if it should hit the ground at a distance of 1km away, the value of g is 9.8 m/s2.

We know that vx and vy0 are equal to
vx = v0 cos θ
and
vy0 = v0 sin θ

From the projectile distance and vx we can calculate the flight time.

t=S/v_x =S/(v_0  cos⁡〖θ_0 〗 )

The flight time can be calculated from V0y and the fact that at the top the velocity Vy = 0 (the total flight time will be twice the value of t, because it contains the motion upward and then back to earth) therfore using the free fall equations we have:

t=2 (v_0y-v_y)/g=(2v_0y)/g=(2v_0  sin⁡〖θ_0 〗)/g

Comparing the two flight times we get:
S/(v_0  cos⁡〖θ_0 〗 )=(2v_0  sin⁡〖θ_0 〗)/g
From the equation the angle is equal to:
tan⁡2θ=(S g)/〖v_0〗^2

Example 2

θ=42.9/2=21.45°