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Glossary of terms you will come across during your Phase 2 training.

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Two contexts here:

Context 1:

Capital letter 'G' refers to gauss, the unit of measurement for the strength of a magnetic field.

Context 2:

In scientific calculations on the course, g represents the acceleration produced in a falling object by the effects of gravity.

An object falling toward the ground will accelerate at the rate of 9.81 metres per second, for every second that the object is falling.
This is represented by: g = 9.81m/s/s or 9.81m/s2

Apprentices will use this figure when calculating the weight of an object, given its mass.

For example, to calculate the weight of a 10 tonne machine, we convert the 10 tonne to the base unit of kilogrammes, 10,000 Kg. This is the mass of the vehicle. To calculate the weight, we use the following formula:

W = m x g

W = 10,000 x 9.81

W = 98,100 Newtons, or 98.1KN

Objects dropped on the earth, regardless of their weight, will fall to the ground and hit the ground at the same time. S

o, in theory, a cannon ball and a feather dropped together, would hit the ground together. Of course, on earth, the atmosphere would distort this experiment.

However, on the moon there is no atmosphere to interfere. Even though the moon's gravitational field is only about 1/6th of that on earth, if the theory is correct, the hammer and the feather should hit the ground at the same time. Check out what happened:


In Plant Vehicle electronics, transistors are used for switching and amplification.

The switching action involves using the base/emitter circuit to switch on and off the collector/emitter circuit.

A second use of the transistor is amplification. It can take a very small input at the base/emitter and amplify it at the collector/emitter circuit. This larger signal can then be used to switch on and off 30 amp relays, or signal the ECU.

The amount by which the base/emitter signal is amplified is said to be the gain of the transistor. For example, the BC109 transistor commonly used on the course has a gain (hFE) of between 200 and 800, meaning that the collector/emitter current can be between 200 and 800 times greater than the base/emitter current.

Read more here about how to check the gain of a transitor


A galvanometer is an extremely sensitive instrument for detecting and measuring electrical current.

A galvanometer must always be connected in series in a circuit, and should only be used to measure very small currents.


The Gas Laws, or Boyle's Law and Charles's Law, cover how the pressure, temperature and volume of gasses are related to each other.

It is important for the apprentice CP Fitter to have a basic understanding of how these factors are inter-related.

For example, when you decrease the volume of a gas, its pressure increases, and so does its temperature.

Why is it important for the apprentice to understand these laws?
One example is how these laws predict and explain the operation of a diesel engine:
Decrease the volume of a charge of air by compressing it with a piston.
As the air is compressed, it becomes very hot.
Into this hot air, we inject a charge of atomised diesel fuel oil.
Because the air is so hot, the diesel begins to burn, thus releasing the engergy contained in the fuel-the diesel engine is now running.

Assorted gasketsGaskets are used to join surfaces together, whenever this joint is required to be leak-proof

Company contact for Hytsu Ireland Ltd.

Unit 1,
Site 22,
Duleek Business Park,
Co. Meath.

  • Mobile: 087 22 56 391

Apprentices: Conor Rock, g2cp12a.

Gasoline Direct Injection. As the name suggests, the fuel is injected directly into the combustion chamber of the engine (not into the inlet manifold).

In the wiring diagrams in AutoData, the abbreviations for colours are in German. German abbreviations for wire colours

Typical gear pumpA gear pump uses the meshing and un-meshing of gears to move liquids like engine oil and hydraulic oil.
The number of turns needed at the input shaft in order to produce one full turn of the output shaft. For example, a ratio of 4:1 means that four full turns are required of the input shaft in order to prodcue one full turn of the output shaft. A ratio of 0.9:1 is called an overdrive. This means that less than one full turn of the input produces one full turn of the output shaft. This is the sort of ratio used in 5th gear in cars.

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