Ilija's+Trebuchet

=**Physics 30 - Trebuchet Project**=

The trebuchet was an effective weapon what they used in the middle ages. They used the trebuchet to brake the wall of castle with projectiles or to throw dead animals over the walls, to spread disease in the castles. The trebuchet uses a counter weight to propel projectiles over a far distance. On one end of the arm ist is a counter weight fixed and on the other end a sling. When the counter weight goes down, the sling swings up, and one end of the sling release and propels a projectile with a great force.

Our project was to design and built a trebuchet was light and uses less counterweight but to get the best performance. The formula for the performance is **P = (d) / (m)(L).** The performance is equal to the distance (how far the ball goes) dived by the mass of the trebuchet times the length of the arm ( included counter weight and sling). __//**Physics principles**//__

Newtons first law: An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Newtons second law: The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

Newtons third law: For every there is an equal and opposite reaction

Projectile Motion: Without air resitance all objects fall with the same acceleration (9.*m/s2). An object projected horzontally will drop on the floor at the same time as an object was dropped. The vertical and horizontal motion of an object do not effect each other

ABS Pipes Bolt String Old clothing Nails Wood Bolt and Nuts for counterweight Hand saw Power Drill
 * __//Materials://__**

__//**Procedure**//__ 1. Planned and designed the trebuchet 2. Cut all pices out of ABS pipes 2. Stick all pices together 3. Drilled two holes for the bolts where arm swings around 4. Cut the arm out of wood 5. Sewed the sling and fixed it to the arm 6. Put some bolts and screws in metal box for the counter weight and fixed to the arm. 7. Test the trebuchet 8. Adjust the mass of the counter weight and the release angle to get the best perfomance.

__//**Test Trebuchet**//__ I tested the trebuchet to get the optimum range by use more or less counter weight and to get a perfect relase angle of the sling. The first tests failed by using less counter weight and because not of the right relase angle. After after a few tests i got the optimum weight and relase angle.


 * Trial || Mass (gms) || Arm Length (cm) || Dist. (cm) || P = d/ml ||
 * 1 || 1950g || 113cm || 420cm || 1.03W ||
 * 2 || 1950g || 113cm || 399cm || 0.98W ||
 * 3 || 1950g || 113cm || 456cm || 1.12W ||
 * 4 || 1950g || 113cm || 531cm || 0.93W ||
 * 5 || 1400g || 113cm || 572cm || 1.26W ||
 * 6 || 1400g || 113cm || 599cm || 1.32W ||
 * 7 || 1400g || 113cm || 581cm || 1.28W ||
 * 8 || 1400g || 113cm || 566cm || 1.25W ||
 * 9 || 1400g || 113cm || 540cm || 1.19W ||