2019 Physics Olympics

---

Gravity

Overview

The WKU Department of Physics & Astronomy is attracting participants to the Western Kentucky Physics Olympics on Saturday, 23 February 2019. Teams of four high school students are invited to compete in this half-day competition consisting of a pentathlon of challenging problem-solving activities that reward teamwork, communication and creativity.

The 2019 Physics Olympics competition will commence with two activities that involve competitors arriving at the event ready to compete with devices they have designed, constructed, and tested. The Siege Engine event requires teams to design, construct, and text a trebuchet that can accurately destroy the enemy targets without harming the neutral structures. The Gravity Vehicle event requires teams to design, construct, and test a vehicle powered only by gravitational potential energy, with the goal of stopping their vehicle as close as possible to a target spot. The "Calculation / Communication Challenge" will require each team to divide into pairs, with each pair creating a statistical rule that their partners can solve, but that will not be understandable to the opponents. The "Impromptu Team Activity" and "Order-of-Magnitude Quiz" will remain cloaked in secrecy until the day of the event.

 

Siege Engine

A trebuchet is a siege engine that that transfers gravitational potential energy into kinetic energy. The energy of the falling counterweight rotates the arm such that a projectile is launched from the sling attached to the opposite, longer, part of the arm.

1. Prior to the competition, each team will design, construct, and test trebuchet devices. There is no weight limit for the siege engine and no restrictions on building materials. There are size restrictions however; it must fit through a standard size door, it must be able to safely fire within the 3-meter tall rooms, and its base must be less than 0.75 meters on a side. The siege engine must be designed and built by the team members, no kits are permitted. There must be no question as to the safety and quality of the siege engine. Entries which are deemed by the judges to be unsafe will not be allowed to launch any projectiles and will receive a score of zero.
2. The siege engine must be powered solely by the release of gravitational potential energy from the trebuchet's falling mass. The use of chemical, electrical, steam, geothermal, nuclear, or internal combustion powered devices are explicitly prohibited. The launch must be achieved by means of a trigger to allow team members to walk away from the siege engine for up to 30 seconds without releasing. The only aspect of the siege engine which may be altered during the siege round is the release angle of the projectile.
3. During the competition, the two trebuchets will be operated by the members of the team. Initially, one, or both, of the trebuchets will be set up at a distance of 4-meters from the center of the target zone. The trebuchets can strike at any targets from this initial distance, but are limited to firing from this distance until the damage control judge verifies the destruction of the three targets located outside the city walls. When the three fortifications the defenders have placed outside the city walls are destroyed, one or both of the trebuchets may be relocated to a distance of 2.25-meters from the center of target zone. The maximum height for any projectile's flight is limited by the room's 3.25-meter tall ceiling. The siege engine will be located within a rectangular launching area with dimensions of 1.70-meters across (along the direction of the rampart wall) by 1.0-meter deep (perpendicular to the rampart wall).
4. The diameter of the protective walls will be between 0.7 and 1.0 meter, and no more than 0.15 meter high (such that the tops of the enemy and neutral structures will rise higher than the top of the walls).
5. The projectiles, knit bean bags sold as Hackey Sack kickballs with a typical weight of 50 grams, will be supplied by the judges.
6. Each team gets a six minute siege round to inflict maximum damage on the defenders, with minimal (ideally zero) damage to the neutral targets.
7. The targets will consist of three simulated defending siege engines outside the walls and four military targets inside the walls, among nine neutral targets.
8. Safety goggles must be worn by all team members entering within a three-meter circle surrounding the launch point. The penalty for violation is immediate forfeiture for the event. Guests/spectators will not be allowed within the 3-meter zone.
9. The ranking will be determined by the sum of the number of military targets destroyed, minus the number of damaged neutral targets, minus three times the number of destroyed neutral targets.
10. The elapsed time required to destroy the three simulated defending siege engines will be used for the first level of tie-breaker.
11. All contestants will ensure that their entry works through the application of physics principles and generally follows the spirit of the competition.

 

Gravity Powered Vehicle

Prior to the competition the participants will design and build a vehicle that uses only the energy from a falling mass to move itself along a straight track, stopping as close as possible to a terminal barrier without contacting the barrier.

1. Teams should design, construct and test a vehicle to travel as quickly as possible any distance from 10.00-15.00 meters without leaving the 2.00 meter wide lane and come to a complete stop as close as possible to the terminal barrier without contacting it.
2. All energy used to propel the vehicle must come from a falling mass not to exceed 1.50 kg. Any part of the device whose potential gravitational energy decreases after the team initiates a run is considered part of the falling mass. The mass need not travel with the vehicle. To facilitate mass measurement, the device must be impounded with the mass detached.
3. When it in the ready-to-launch configuration the entire vehicle (including the falling mass) must fit into a 0.75 m cube. No part of the vehicle or its energy propulsion system may extend more than 0.75 m behind the starting line prior to the team initiating the run.
4. Energy from the falling mass may be transferred to other energy storage devices, but those devices must be in their lowest energy state prior to initiating the run. The vehicle may not contain any electrical/electronic devices.
5. Additional sources of mechanical energy may be used to stop the vehicle, however, it may not be remotely controlled or tethered in any way to guide it or to make it stop. The stopping mechanism must work automatically and be contained completely within the vehicle.
6. The only liquid substance teams may apply to the surface of the vehicles wheels is water provided by the competition coordinator. Substances may be applied to other parts of the transport provided they do not leave residue on the track and/or event area.
7. If used, sighting/aligning devices must be attached to the vehicle and/or energy propulsion system and remain installed during a run.
8. The competition will be on a straight and level 2-meter wide lane marked on a relatively smooth, hard, low friction tile floor. A terminal barrier extending completely across the lane will be located at a randomly chosen distance between 10 and 15 meters from the starting line. The actual distance will not be announced until just prior to the start of the event, after all devices have been impounded.
9. The entire vehicle must be impounded before the start of the event and will be released from impound when the team is called to compete. Once teams enter the event area to compete, they may not leave the area or receive outside assistance, materials, or communication until they are finished competing. Each team has a total Event Time of no more than 10-minutes to make up to 3 official runs with their vehicle.
10. The time starts begins once the team has moved to the starting line, and ends when the 10-minute time expires, the last official run is complete, or the vehicle is deemed unable to compete. A run may be completed if the mass has been released before the 10-minute time expires. Once the vehicle is setup in ready-to-launch configuration on the track, the judge may pause time to verify construction. Once verification is complete the Event Time shall resume.
11. Students may not back up the transport device on or near the track to set the distance into the stopping mechanism. Teams may adjust their device, but they may not increase the falling mass once it has been measured.
12. Prior to the beginning of each run, the front of the vehicle will be placed even with any point along the width of the starting line. All of the vehicle's wheels must be on the floor at the start.
13. The Run Time starts when the mass or the vehicle is released and ends when the egg transport comes to a complete stop. Either the vehicle or the falling mass, but not both, may be held and released by the team to initiate the run. The mass and device may not be pushed or pulled to start it. All energy must come from the falling mass.
14. Once the team initiates the run, they may not control or touch the vehicle in any way until it has come to a complete stop. Participants may not be on the track until after the judge has completed all measurements.
15. Runs will be assessed one Run Penalty for each of the following:
• Any part of the vehicle makes contact with the barrier.
• Any part of the vehicle runs outside of the lane at any point of the run.
• The vehicle fails to travel at least one-half of the announced track distance.
• Any other event rule that does not have a specific penalty is violated.
16. One Construction Penalty will be assessed for each rule that is violated.
17. Teams will be ranked in three tiers using the single run (including run penalties and construction penalties for that run only) that will give them the best overall place (low score wins), where:
• Performance Value = sum of best two [Run Times (in seconds) + Stopping Distance (in cm)]
• 1st Tier: Runs with no Penalties will be ranked by their Performance Value.
• 2nd Tier: Runs with Run Penalties, but no Construction Penalties, will be ranked by: Performance Value x (# Run Penalties).
• 3rd Tier: Runs with Construction Penalties will be ranked by: Performance Value x (# Construction Penalties + # Run Penalties)

 

Communication/Calculation Challenge:

Details of the Communication/Calculation challenge will be posted here soon. Please check back for updates.

 

Impromptu Team Activity

Activity is the key word for this competition, with the goal being for each team to achieve the desired results as quickly as possible. The instructions regarding this event are not released until it begins, so everyone is on equal footing. The situation is designed to reward teamwork and common sense thinking as well as knowledge of physics. Every team will come away with smiles and good memories regardless of how well they master the particular challenge.

 

Order-of-Magnitude Quiz (also known as Fermi Questions)

Arrive at a reasonable approximation for the value of a complex situation with very little to no information available to directly compute the answer. In this quiz, the contestants will need to quickly make assumptions for values to use in simple calculations in order to arrive at the "correct" answer, stated as the power of ten of the number that fits the accepted value.

Teams will receive 9 questions to complete within 15 minutes. The teams can divide the work in any way they see fit, but only one answer per question per team will be accepted. Answers will be judged according to how many orders of magnitude the team's answer is from the judge's solution. The lowest score wins -- 0 points awarded for the answer accepted by the panel of judges, with 1 point scored per order of magnitude from the accepted value.

Examples of Order-of-Magnitude Quiz questions include:

• How many electrons enter the starter motor when a new, full-sized pickup starts?
• How many times would a tire of a Ford Taurus rotate when driven from NYC to LA?
• Estimate the number of gallons of gasoline used annually by all the cars in the USA.