ASVABStudy Topic
ASVAB Technical Foundations Study Guide
Review introductory electricity, mechanical advantage, gears, hydraulics, tools, automotive functions, and physical principles.
Topic Overview
Keep electrical quantities distinct
Current is measured in amperes, voltage in volts, resistance in ohms, and power in watts. For an ideal resistor, I = V/R; for the stated simple load model, P = VI. Series resistances add. Parallel paths reduce equivalent resistance below either of two positive individual resistances. An open series path interrupts current in the ideal circuit.
Balance force, distance, and rotation
A lever balances when opposing torques match. Torque from a perpendicular force equals force times distance from the pivot. In an ideal machine, a force advantage requires a corresponding increase in effort distance; energy is not created. Meshed external gears turn in opposite directions, and the gear with more teeth turns more slowly. For a 20-tooth driver and 60-tooth driven gear, the driven speed is one-third of the driver speed.
Understand components by function
A radiator transfers heat from coolant to air, a crankshaft converts piston motion into rotation through connecting rods, and lubricant reduces friction between moving parts. A micrometer measures dimensions; a wrench applies torque to suitable fasteners. These are conceptual questions rather than instructions for repairing energized or moving equipment. For calculations, note assumptions such as ignored friction, constant pressure, or no slipping, and keep units consistent throughout.
- Confusing voltage, current, resistance, and power units.
- Adding parallel resistances as though they were in series.
- Assuming mechanical advantage creates energy.
- Ignoring ideal-model assumptions or the chosen pivot.
Checkpoint Quiz
Test your understanding of ASVAB Technical Foundations
These questions are for study practice only and are not official exam questions.
1. What is the principal purpose of engine lubricating oil?
2. Which material is generally a good electrical conductor?
3. A force of 40 N acts perpendicular to a wrench 0.25 m from the pivot. What torque is produced?
4. What does a thermostat primarily do in a temperature-control system?
5. An ideal 12 V source is connected across a 6 ohm resistor. What current flows?
6. An ideal lever has a load arm of 2 feet and an effort arm of 6 feet. What effort balances a 90-pound load?
7. What is the function of a vehicle's radiator in its cooling system?
8. Which unit measures electric current?
9. Two resistors of 3 ohms and 5 ohms are connected in series. What is their total resistance?
10. Two identical 8 ohm resistors are connected in parallel. What is their equivalent resistance?
Frequently asked questions
Why does a larger driven gear rotate more slowly?
Each revolution requires more teeth to pass the contact point, so its rotational speed is lower for the same tooth-motion rate.
How is ideal hydraulic output force found?
Find pressure from input force divided by input area, then multiply that pressure by output area.
What is the tradeoff in an ideal force-multiplying machine?
The effort moves farther than the load, preserving work when losses are ignored.
Are these service instructions?
No. They explain introductory functions and ideal models for study, not procedures for maintaining real equipment.
