Number of Participants: 2
Approximate Time: 30 minutes
Description:
Students will build, calibrate and fire their own free-standing (not handheld) trajectory device that must be capable of propelling a tennis ball at a target placed between 2 and 7 meters.
Competition:
- Each team will bring their homemade catapult to the competition site immediately upon arrival at the site of this year’s event. Please print your school’s name prominently on the catapult. Testing or practicing at the event is not allowed.
- A “regular” tennis ball will be used in this year’s event. Tennis balls will be provided.
- A data chart showing the launching characteristics of the catapult and tape measure can be used and is recommended. Tools and spare parts may be useful.
- The ball may be shot, slung, or lobbed at the target. The “launch force” must be provided by gravity or elastic solids, (such as springs, rubber bands, bungee, etc.). The last point on the device touching the tennis ball may not be more than 50 cm above the ground before, during and after shooting the tennis ball. Exception: for trebuchet-type designs, the flexible sling may swing higher than 50 cm during launch as long as the rigid arm attached to the sling does not exceed 50 cm.
- Each catapult should be designed and built by the students with minimal adult assistance. They should be made to operate safely at all times. Participants should be knowledgeable of the characteristics and safe operation of their catapult.
- The catapult will sit on the ground and be fired at the target, also at ground level. The target will be a clearly marked point in the center of a sand filled area approximately one meter in diameter.
- The distance from the shooting line to the center of the target will be between 2m -7 m. The actual distance will be announced the day of the event. Participants may place their catapult at any point behind the shooting line, up to 2 meters.
Scoring
The contestants will have 6 minutes to fire their catapults five times. Each team will have two practice shots and three scoring shots. The distance from where the tennis ball initially lands to the target will be measured in centimeters after each shot.
Teams will be allowed to make adjustments following each shot. Hitting the “bullseye” will be scored as a zero, while missing the sand filled area entirely will be automatically given a score of 150 cm. The cumulative distance after 3 scoring shots will be the team’s score.
The smallest score wins.