# Trebuchet Circular Motion -> o.0

I make trebuchet for my physics project and i need to calculate the distance it fires and compare it to my acctual firing.

I know how to use the non vertical equations for circular motion but i dont know which equation to use for this.

I can calculate the projectile motion after i have the velocity.

Mass = 2.5kg
CounterWeight Arm lenght = 16cm (ie. radius)
Circumpherence it travells = 1/3 of circle.

The counterweight arm only swings 1/3 of circles circumpherence.

All i need to know is the equation because i can use the non vertical motion equation but then i would have to guess the time it takes.

And i want to calculate the time not guess . ))))

HallsofIvy
Homework Helper
One of the things you will have to know is the speed of the treguchet arm itself- how fast does it go through that 1/3 circumference?

Basically i thought thats wat i need to find out using the equation.

I used a different equation and i found the acceleration of the counterweight arm to be 8m/s/s so if the counterweight arm is 1:3.65 ratio then that means the load arm will be accelerating @ 3.65 times faster than the counterweight arm?

If so. What other equation will i need to know to find out time and final velocity.

I could use linear equations of motion but i thought that the circular will make a slight difference?

So which equation would i need since i now have

Acceleration = 29.2m/s/s
Distance 1/3 of circumpherence (radius = 50cm) (2*pi*r = 2 * 3.14 * 50) = (314cm) (314 divided by 3 = 104cm)

So the distance it has to cover is 104cm

So if i have those two will i be able to find out the final velocity of the load arm?

kk dont bother replying. Assignment due in acouple hours. :)

Ciao all I figured it out anyway