Heat Conduction and Convection

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What is ignition temperature?

The maximum temperature needed to initiate combustion

The average temperature at which a material burns

The minimum temperature needed to initiate self-sustained combustion (correct)

The temperature at which a substance starts glowing

What is adiabatic compression?

Compressing a gas to generate light

Producing heat by compressing a liquid or gas (correct)

Cooling a liquid or gas by compressing it quickly

Expanding a gas to increase its temperature

What can cause spontaneous heating?

External heat sources

Contact with cold surfaces

Lack of oxygen

Oxidation giving off heat (correct)

Under what conditions can spontaneous heating lead to ignition?

When the material insulates more heat than it dissipates Signup and view all the answers

What are hypergolic mixtures mainly used for?

To propel missiles or rockets Signup and view all the answers

How are friction sparks created?

When two hard surfaces touch with sufficient force Signup and view all the answers

Which method of heat transfer involves the movement of air or liquid?

Convection Signup and view all the answers

Which of the following is a good heat conductor?

Aluminum Signup and view all the answers

What is the major source of fire spread influenced by convection?

Heat movement from floor to floor Signup and view all the answers

Which product is released as heat and flame when a fuel burns?

Thermal energy Signup and view all the answers

What is the main difference between heat waves (infrared rays) and light waves?

Length Signup and view all the answers

Which method of heat transmission involves the transfer of energy as an electromagnetic wave without an intervening medium?

Radiation Signup and view all the answers

What is the main difference between gases and vapours in terms of volume?

Gases do not have specific volume, while vapours tend to assume the shape of their container. Signup and view all the answers

What will happen if a gas or vapour has a vapour density less than air?

It will rise and tend to dissipate. Signup and view all the answers

Which components are described by the Fire Triangle as necessary to create fire?

Oxygen, heat, and fuel Signup and view all the answers

What happens if any one of the components in the Fire Triangle is removed?

The fire cannot exist. Signup and view all the answers

What does the Fire Tetrahedron provide an explanation for?

Why certain chemicals burn in the absence of oxygen. Signup and view all the answers

Which of the following is NOT one of the components of the Fire Tetrahedron?

Heat Signup and view all the answers

What does the numeral in the fire extinguisher classification indicate?

The fire extinguishing potential of the extinguisher Signup and view all the answers

What does the letter in the fire extinguisher classification refer to?

The class of fire the extinguisher is designed for Signup and view all the answers

How is 'appreciable depth' defined in relation to flammable liquid?

A depth greater than 6 mm Signup and view all the answers

What does a 'dual or triple classification' on a fire extinguisher imply?

It can be used for multiple types of fires Signup and view all the answers

What is the basis of fire extinguisher classification according to the text?

Physical fire extinguishing potential Signup and view all the answers

How does an expert compare to a novice in terms of fire extinguishing capacity with the same quantity of agent?

An expert can extinguish more fire than a novice Signup and view all the answers

Which extinguishing agent absorbs more heat per volume than any other agent?

Carbon Dioxide Signup and view all the answers

Which type of fire extinguisher is generally safe only for Class A fires and is electrically conductive?

Dry Powder Signup and view all the answers

Which type of foam has excellent wetting and penetrating properties due to low surface tension?

Class A Foam Signup and view all the answers

What can happen if water is used as an extinguishing agent in a confined or unventilated space?

Cold shock to electrical equipment Signup and view all the answers

What is one limitation of Dry Chemical extinguishers?

Leaves a residue Signup and view all the answers

What is the primary advantage of Wet Agents in fire extinguishing?

Saponification turns oils and fats into soap/foam Signup and view all the answers