Principles of Technology

Unit 1: FORCE

Unit Objectives:◦ Describe in your own words, what force is.◦ Give examples of complex technological devices where

force must be controlled, measured, or applied◦ Describe what force, pressure, voltage and temperature

difference have in common◦ Describe or predict what happens to an object when

forces on it are balanced and when forces on it are unbalanced.

◦ Measure force in mechanical, fluid, electrical and thermal systems.

◦ List occupations that require technicians to measure, control, or otherwise deal with force in complex devices.

Force

Forces are a part of our everyday activities Mechanical, fluid, electrical and thermal

energy systems involve forces. A prime mover, such as an unbalanced

force, pressure difference, voltage difference, or temperature difference, causes whatever it “acts” on to move.

Mathematics is essential for technicians working in advanced-technology occupations.

Main Ideas

Force is a push or a pull.

What is force?

A force can◦ Cause an object to start moving or to move

faster◦ Cause a moving object to change direction◦ Cause an object to slow down or to stop

moving◦ Change the shape of an object

What can force do?

Force is what makes things move in a mechanical system.

In a mechanical system, force is called the “prime mover.”

What are the four energy systems?

Each system has a prime mover that acts very much like force.

Other important energy systems

Energy Systems Prime Movers

Mechanical Force

Fluid Pressure

Electrical Voltage

Thermal Temperature Difference

Automobile◦ Mechanical – Pistons, connecting rods, crankshaft◦ Fluid Systems – Hydraulic system transfers motion

from the brake pedal to the brake shoes◦ Electrical system – battery, alternator, spark plugs◦ Thermal – or cooling system – radiator, fan and

thermostat, water pump, liquid coolant,

Energy Systems in Combination