Presentation on theme: "MESA Day 2012 Mousetrap Car - Distance"— Presentation transcript:
1MESA Day 2012 Mousetrap Car - Distance 6th-8th Grade
2Objective & MaterialsStudents will build a vehicle solely powered by a standard mousetrap to travel the longest distance on a specified trackMaterials:1 standard mousetrapAll other materials are legalNO KITS!
3First Things First: READ RULES AT LEAST TWICE!! Mousetrap is ONLY source of energyDon’t tamper with mousetrap:No paintNo decorationAlteration allowed ONLY for attaching mousetrap to chassisSpring may not be altered
4Let’s review physics! Energy: It’s what moves the car. Potential: energy stored in a systemElastic & GravitationalKinetic: energy of motionPotential KineticInertia: The resistance an object has to changing its state of motion.Rotational Inertia: The resistance an object has to changing its state of rotation.Friction: A force that opposes the direction of motion.Static: caused from two surfaces pressing together.Fluid: caused from liquids or gases. In air, this is known as drag.Torque: The force required to rotate an object.Power: The rate at which energy is released or transformed in a system.
5The Engine: Spring + Lever Arm Energy from spring is transferred to car via the lever armLever arm provides torque required to turn axlesLength of lever arm affects power outputShorter arm = faster outputLonger arm = slower output
6Wheels & Axles # of wheels : 3 or 4 Wheel radius Wheel grip (traction) The greater the radius, the greater the torque required to rotate the axleWheel grip (traction)Power output must match wheel grip to avoid spinningAvoid wasting energyRatio of wheel-to-axleLarger ratio good for distanceFrictionReduce friction between wheels and surfaceAlso between axle and chassisAlignment
8The Chassis The body of the car Balsawood, plastic, other lightweight materialsMassThe heavier the car, the greater the friction force with the surfaceMore force required to actually move the carLong chassis vs. Short chassisNarrow vs WideAerodynamic (reduce drag)
9Fast vs Slow Fast: Slow: Build a car that will accelerate quickly and “coast” as far as possibleshorter lever armsmaller wheel radiusquick power outputSlow:Build a car that will accelerate slowly over the entire distance that it travels. Less “coasting”.longer lever armlarger wheel radiusslow power output
10Remind Students: Research, research, research! Experimentation is the keySet a working timelineREAD THE RULES….twice….again!!HAVE FUN!!!: It’s not the end of the world.