- Projectile Motion
- 25 Jan 2015 10:27:06 pm
- Last edited by MrDew25 on 07 Feb 2015 11:48:31 pm; edited 1 time in total

Hey guys. I know I haven't been on in a while and that is just do to school and work, but I need your help. Some of you may know my projectile motion program that I had made (some of you may have even downloaded it!) and read in the readme.txt that that program didn't account for air resistance.

After some time, I found some equations that seemed to work at first, but than didn't when I tested them more closely. These equation I will post at the bottom of this post.

If anyone of you is smart enough to help me find an actual, working equation for the motion of a projectile being shot, accounting for air resistance, I will thank them immensely and if and when I put that program online, I will have you as the author (if I can't do that, I will list you as co-author and in the description say that this is your program).

Here are the two equations:

x(T) = (M/K)Vcos(theta)(1-e^(-KT/M))

y(T) = (-MGT/K)+(M/K)(Vsin(theta)+(MG/K))(1-e^-KT/M))

Variables:

M: Mass

G: Gravity (9.81m/s)

V: Initial Velocity

theta: Angle

K = (MG)/sqrt((2mg)/(CPA))

C: Drag Coefficient

P: Air Density

A: Area of the Projectile

Edit: I must mention that this is for a trebuchet project tau my physics class is doing. We want to try to launch an object into something.

After some time, I found some equations that seemed to work at first, but than didn't when I tested them more closely. These equation I will post at the bottom of this post.

If anyone of you is smart enough to help me find an actual, working equation for the motion of a projectile being shot, accounting for air resistance, I will thank them immensely and if and when I put that program online, I will have you as the author (if I can't do that, I will list you as co-author and in the description say that this is your program).

Here are the two equations:

x(T) = (M/K)Vcos(theta)(1-e^(-KT/M))

y(T) = (-MGT/K)+(M/K)(Vsin(theta)+(MG/K))(1-e^-KT/M))

Variables:

M: Mass

G: Gravity (9.81m/s)

V: Initial Velocity

theta: Angle

K = (MG)/sqrt((2mg)/(CPA))

C: Drag Coefficient

P: Air Density

A: Area of the Projectile

Edit: I must mention that this is for a trebuchet project tau my physics class is doing. We want to try to launch an object into something.