-         Determine the list of applicable PT items in a finite world item

-         ITEM/STEPS: Survey/screen a motor vehicle noting applied PT items listed. Each student/team would make a table of the below PT lab items that can be found on/in a motor vehicle. Even though the lists would be somewhat different for each vehicle surveyed, the overall tables should match to a large degree. NOTE: the below list states the name of the individual PT labs followed by possible devices that apply to the general category. However, this real-life application listing will be fun to examine as students “grow the list.”

o       Mechanical Forces and Springs: various springs and linkages in the motor compartment and spring release in the trunk and gas cap cover

o       Measuring Specific Gravity: The strength of battery acid and antifreeze is determined by measuring the specific gravity.

o       Voltage and Measuring Voltage: The strength of the electrical system of a vehicle is determined by the voltage of the system.

o       Temperature Difference and Specific Heat of Metals: Cooling systems have thermostats that open and close as antifreeze temperatures change

o       Measuring Torque and Doing Work with a Wheel and Axle: There a various pulleys in a vehicle with an associated belt drive and the wheels are all fitted with an axle. Additionally, the wheels are balanced with lead weights to even out the torque. Other wheels and pulleys are window assemblies, and steering wheels

o       Work Done in Lifting a Fluid: This is a challenge as the antifreeze is pumped through the system, but the brake fluid is in a closed system of hydraulics. However, the automatic transmission could be examined along with fuel lines and fuel pumps, and windshield washer systems

o       Measuring work done by an Electric Motor: The window motors could be examined along with an antenna motor. The data from a winch would be an excellent teaching tool. Additionally, the starting motor could be included in the survey and work calculated.

o       Measuring Average Velocity and Average Acceleration in a Mechanical System: This observation could only be obtained with a licensed driver and at low speeds. 

o       Measuring Liquid Flow Rate in a Channel At first glance one might not think this lab applies, but any exterior channel that directs rainwater off the roof would be applicable. Perhaps the tread channels on the tires could be examined to see how this lab applies.

o       Measuring Rate in a DC Electrical System: The overall electrical system in the vehicle could be examined. It might be beneficial to break it out into components: radios, ignition, lights, etc.

o       Creating Steady-State Heat Flow Conditions: This applies to the antifreeze/cooling system, the interior A/C or Heating and maybe even to the running temperature of the tires.

o       Determining Kinetic Coefficients of Friction in Mechanical Systems This applies to any moving entity in the vehicle: tires, pistons, cam shafts, transmission, window edges in the guides, and any hinges.

o       Measuring Resistance to Fluid Flow in Tubes: A vehicle has numerous tubes: brake lines, fuel lines, windshield washer fluid/lines, exhaust systems

o       Resistance in Series and Parallel Circuits (Ohm’s Law): This applies to all the electrical systems hooked into the fuse box of a vehicle. A survey would reveal which are in series and which are in parallel.

o       Determining the Thermal Resistance of a Material This applies to all systems in a vehicle attempting to conserve hot/cold temperatures. The heating and cooling systems come to mind. But, also the rate of heat loss/gain to the vehicle through the glass and body materials could be measured.

o       Using Energy in Compressed Air to Operate Air Motors: This applies to older vehicles that utilized compressed air to drive the windshield wipers. Additionally, if the vehicle has compressed air brakes or other devices driven by air such as springs they could be examined.

o       Measuring Energy Stored in a Compressed Spring: This applies to the “sleeping” springs that open/close various compartments/doors in the vehicle

o       Energy stored in the Magnetic Field of an Inductor: This applies to any vehicle equipment that depends on an induction coil to operate when excited by the DC current. 

o       Equilibrium Temperature of a Mixture: This applies to the cooling system of the vehicle. This is especially important when added a cold replacement fluid to a hot radiator: RUN THE ENGINE AND STIR. One might examine adding cold gas or cool engine oil and calculate/note any temperature changes.

o       Measuring Linear Mechanical Power: This applies to any electrical motor doing work in the vehicle. The starting motor, the electric window motors, and even the front-end winch apply.

o       Measuring the Power Developed by an Air Motor: As stated earlier, this applies to older vehicles with air driven windshield wipers. However,

o       Measuring Power in Electric Motors and Generators: Again, as stated above this would apply to any electrical motor doing work in the vehicle. The starting motor, the electric window motors, and even the front-end winch apply.

o       Weight Distribution and Momentum in Rotating Systems: Again, rotating systems would be examined: tires and balancing weights, steering wheels, fly wheels and any pulleys.

o       Resonance of Sound Waves in Hollow Tubes: This applies to any sound generator in the vehicle. It encompasses the horn (i.e. is it at resonance and LOUD) and the sound system in the interior.

o       The Electromagnetic Spectrum: This applies to all the various wavelengths emitted by the various electrical components of the vehicle. The sparkplugs, turn signals and associated wires emit a specific spectrum. This brown noise can be measured by instruments and even AM radio channels. A survey of the how much electromagnetic energy passes through the windows and how much heat passes back could be completed. Additionally, the heat spectrum could be measured the vehicle as a whole.

o       Nuclear Radiation This would apply to any component emitting radiation. A survey with a Geiger counters could bring them to light.

o       Reflection of Light This applies to any tinted windows, reflective materials and could even be extended to cover the reflections from road signs. The types of headlights could be examined as to which type of bulb produces the best reflection. Additionally, the type of glass and the angle to the interior could be examined as to how much light enters the passenger compartment.

o       Lens Experiments This applies to all the lenses in the vehicle associated with lights. However, the headlights are the ones that are focused more so than the others.

o       Laser Radiation: This lab item may not apply to a vehicle directly, since lasers are not installed. However, students could extrapolate this item to garage door sensors, intersection cameras etc.