Heat Test

The First Law of Thermodynamics states that Energy can never be created or destroyed Energy can only change forms such as Potential Energy to Kinetic Energy

this law is also known as the Law of the Conservation of Energy

Heat is the form of energy that is transferred between systems, objects, or areas with different temperatures

Heat will generally move from objects or areas that have higher temperatures to objects or areas that have lower temperatures The transfer of heat will continue until equilibrium has been achieved where both objects or areas have the same temperature

The term Temperature is the measure of the average energy of motion of the particles of a particular substance, which is affected by heat e.g. ice has a lower temperature than water because there is less heat affecting the water molecules compared to the water

There are 3 main forms of transferring heat between objects : conduction, convection, radiation

One form of transfer is Conduction, which is the transfer of heat directly from one object to another e.g. stove heating up a pot of water

A second form of transfer is Convection, which has heat moving through a liquid or a gas e.g. warmer air rises, and cooler air falls

The third form of transfer is Radiation, which has heat being transferred by electromagnetic waves e.g. heat felt from a fire without having to touch it

Most substances will have three main temperature points: Freezing point Boiling point Ignition point

point where it turns from liquid to solid

point where it turns from liquid to gas

temperature at which a substance will combust

Example: Ethanol Freezing Point = (-114)℃ Boiling Point = 78℃ Ignition point = 365℃

Some substances, such as water, does not have an ignition point because it cannot be further oxidized or burnt

From an Energy Conversion standpoint, the Law of Entropy states that when energy is converted into another form of energy, not all the energy is converted into that new form of energy This Law is also known as the Second Law of Thermodynamics

Example: Turning on an incandescent light bulb When electricity is converted within the light bulb to create light energy, the majority of the energy is converted into heat energy in the process Heat is usually the traditional “waste” of most energy transfers

There are several mechanisms that humans have created that allow humans to utilize heat transfers in more constructive ways instead of being the byproduct of energy transfers

One mechanism is the Heat Pump Heat Pumps allow for machines to make heat flow from one area to another area Example: The Compressor of a Refrigerator forces coolants to circulate and remove heat from within the refrigerator and transfer that heat away from the refrigerator

Another mechanism is the Heat Engine The Heat Engine is designed to convert Heat Energy into Mechanical Energy Example: Steam Engines The Boiler in steam engines allows for the heating of water, which will create an expansive gas that drive a piston to move

Absolute Zero is the coldest theoretical temperature in our Universe It is (-273.15)℃

As temperatures decrease, the amount of kinetic energy decreases at the molecular level According to Classical Mechanics, Atoms may stop moving at Absolute Zero According Quantum Mechanics, Atoms can never stop no matter how cold the temperature

According to the Third Law of Thermodynamics, the Entropy of an Object continues to lower as it approaches Absolute Zero However, an object will never reach Zero Entropy

When the Human Body experiences cold, the warmth of the body diffuses with the cold, which removes heat from the body The Human Body will radiate heat naturally into its environment if the temperature is below 20 degrees Celsius At temperatures above 20 degrees Celsius, the body encourages Heat Removal through Perspiration, which cools the Body through Evaporation