Question | Answer |
Abrupt Stop | When a gravity cruiser comes to a stop because its string is attached to the axle and has been pulled taut |
Ballast | Extra weight added to the chassis as necessary to keep the cruiser's wheels in contact with the ground |
Axle Winds | The number of times the string can be wound about the drive axle as the weight is lifted to its highest position; the winds are a function of axle diameter and the distance between the weight's highest and lowest positions |
Calculated Distance | The distance the cruiser is expected to travel, assuming the string unwinds from the axle completely and the cruiser does not coast beyond that point |
Chassis | The body of the gravity cruiser, consisting of axles, wheels, and base platform |
Circumference | The distance around a circle |
Coasting Stop | When a gravity cruiser gradually slows to a stop after its string has become completely unwound and is disconnected from the axle |
Diameter | The distance across a circle, measured through its center |
Drive Axle | The axle around which the string is wrapped |
Force | A push or pull on an object |
Friction | Rubbing between two surfaces, which causes energy loss |
Fulcrum | The pivot point around which a lever rotates |
Hypothesis | An untested idea about how things work |
Inertia | The tendency of an object to resist changes in motion |
Kinetic Energy | The energy an object has due to its motion |
Lever | A bar that pivots about a fixed point (a fulcrum) |
m | metric unit for the meter |
Moment Arm | The magnitude of force applied to a rotational system at a distance from the axis of rotation (the fulcrum) |
Momentum | The product of mass and velocity; the more a gravity cruiser has when the string disconnects from the axle, the farther it will coast before stopping. |
Pi | The ratio of the circumference of a circle to its diameter; which is approximately 3.14 |
Potential Energy | The energy stored in an object |
Prototype | An experimental version of a design or product |
Torque | A turning or twisting force |
Travel Distance | The actual distance a gravity cruiser travels during a trial without extra pushes or extra help ( compared with calculated distance) |
Troubleshooting | The process of systematically determining reasons for malfunctions and finding ways to fix them |
Weight | (In this case) The pennies attached to the lever; the magnitude of the weight is equal to the mass of the pennies multiplied by the acceleration of gravity |