TREBUCHET Report Grading

Trebuchet The report will included the following information: (1) a word processed document, size 12 font, doubled spaced, (2) a very brief history on the trebuchet, (3) Physics based principles on how and why the trebuchet operates, (4) description on how the team designed, collected, assembled, and tested their trebuchet, (5) show calculations on computing trebuchet force, (6) data table showing team test results, (7) information on how much money is used in the building of the trebuchet, (8) correct writing method and procedures used in the report, (9) bibliography and internet sources listed.

Trebuchet Typed report – 20pts Brief history – 20pts Physics based principles – 20pts Physics calculation – 20pts Design & assembly – 10pts Blue prints / pictures – 10pts Data Table (test) – 50pts Cost of project – 10pts Bill of Material – 10pts Correct writing – 20pts Bibliography – 10pts Possible 200 points

Trebuchet Formulas Torque on the counterweight and projectile T= L x F Potential Energy of the counter weight E p = W x h or E p = m x g x h Kinetic energy of the projectile E k = ½ w/g x V 2 or E k = ½ m x V 2 Speed of the projectile V = D/t Acceleration of an object V f – V i / t Efficiency = Work out / Work in x 100%

Trebuchet Bill of Material looks like this Trebuchet 2” x 4” x 8’0” $3.25 = ” x 10” x 10’0” $ 9.00 = ” dia. X 4’0” $2.00 = ” x 4” x 8’0” $ 8.00 = 8.00 ¾” dia. x 25’0” rope $6.00 = 6.00 Screw eyes 5/8” x 2”.75 = 2.25 Bolt ½ x 6” 1.25 = 1.25 nails 3” 3.00 = 3.00 Total Cost per team member 60.00/4 = 15.00

Trebuchet Calculations Counter weight / projectile mass Conversion lb x.453 = kilograms Distance feet to meters Conversion ft x.3048 = meters Gravity Metric = 9.8 m/sec 2 Gravity English = 32 ft/sec 2 Potential Energy – English E p = w x h Potential Energy – Metric E p = m x g x h Velocity = Distance / time Acceleration a = V f – V i / t Kinetic Energy – English E k = ½ w/g x v 2 Kinetic Energy – Metric E k = ½ m x v 2 Torque = F x L Work = T x Ɵ Mechanical Efficiency = Work out / Work in x %

Trebuchet Graph – should look like this.

Trebuchet throw Distance ft. Distance MReason Lengthen sling Lengthen sling Lengthen sling Lengthen sling Bent nail Changed sling New nail / Hook More weight More weight More weight Data Table should look like

Trebuchet P.O.T. - Trebuchet Project Pts. Team 5th Design - 50 Constructi on - 50 Distanc e-50 ExtExt Dist pts. Tot al% 1 Brooklyn, Sarah, Dillan, Brittany Nic, Sol, Tommy, Ray Kip, Mark Tyson, Josh, MaCauley, Tate Amy, Sarah, Luke Zack, Jon Garett, Garett, Daniel, Kevin Emily, Rachel, Sherry, Brianna, Ashley Becky, Brianna C., Kilee Billy, Divet

Bibliography Gurstelle, William The Art of trebuchet, Chicago Review Press 2004

Trebuchet Extra Credit Kilt – 10 point Hit the Monster – 10 Crazy Hat – 10 (has to really be good) Over 10 meters (32 Feet) – 2 points for every meter ( feet) over.