Heat and Temperature, Essay Example

The zeroth law, the first law, the second law, and the third law are the four laws that make up thermodynamics. “Thermodynamic equilibrium and temperature” is the zeroth law. “Work, heat, and energy” is the first law.

The gas laws can be understood using Kinetic Molecular Theory, which explains the macroscopic properties of gases. Gas particles are continually in motion and undergo fully elastic collisions, according to Kinetic Molecular Theory. The elastic potential energy of a group of gas particles is determined only by absolute temperature. According to Kinetic Molecular Theory, the average kinetic energy of the molecules rises as the temperature rises. The particles have a higher chance of colliding with the container’s edge as they move quicker.

The terms heat and temperature are not the same thing. The total kinetic energy of a substance’s atoms is known as heat energy. Temperature is defined as the average kinetic energy of a substance’s atoms. There are three mechanisms that aid heat transfers, and these include; conduction, convection, and radiation. Conduction is a process of transferring heat energy from one place to another whereby heat energy is conveyed through collisions between nearby atoms or molecules. The other two types of heat transport are radiation and convection. The rate of energy transfer by conduction is faster when the temperature difference between the substances in contact is large. Materials with higher relativity conductivity, such as iron and silver, tend to be good conductors, while those with low conductivity have slow conduction. Insulators are materials that are poor electrical conductors, such as glass and plastic. A poor conductor is something that can’t easily conduct heat or electricity (or both) like a conductor.

Heat Pumps transport heat from a low-temperature source to a higher-temperature source, which is subsequently transferred into a home for heating and hot water. This can be done quite efficiently, with the heat production reaching up to five times the amount of electrical energy supplied. In a heat pump, the energy arriving in high temperature is equal to sum of the energy from low temperature region and the work needed to move it. Temperature conversion equations can be used to convert temperatures from one scale to another. 

Irreversible processes, such as viscous dissipation, are actual processes carried out in finite time using real substances having internal temperature, pressure, and/or velocity changes that cause energy dissipation. Real process is equivalent to the irreversible process. In addiotn, the measures of disorder equals entropy. The total entropy of the universe continues to increase, according to the second law. Furthermore, natural processes degrade coherent, useful energy, resulting in the universe’s accessible energy dwindling and, eventually, the universe’s heat death. Molecular motion is the movement of component particles or molecules in a certain direction. The effects of heat and temperature on molecular motion are significant. This is because temperature is a measurement of a molecule’s average kinetic energy and hence reflects molecular mobility.

Energy connected with electromagnetic waves is known as radiation energy. It has the ability to work in a vacuum. Furthermore, all objects produce and absorb radiation. Temperature, on the other hand, regulates the rate of emission, the intensity of radiated light, and the type of radiation released. In addition, the temperature is determined by calculating the difference of emission and absorption rates. Mass, temperature change, and material type are all factors to consider during heating. To achieve the same temperature, various materials require varying quantities of heat. The calorie, an older metric unit, and the British thermal unit (Btu), an English measure common in the United States, are the two most often used units for measuring heat. Heat is measured in joules, which is a universal unit of energy measurement.

The first law of thermodynamics asserts energy cannot be created nor destroyed but only altered in its form. This is represented as JQ-W=U_2-U_1. The second law of thermodynamics asserts the total entropy of an isolated system cannot decrease. Based on the two laws, there is always conservation of energy, and secondly, the efficiency of any machine can never be 100%. Convection entails the movement of heat through bulk motion of the hot material such as water or gas.

The movement of molecules/atoms is highly dependent on the phases of matter. In solids, the atoms or molecules tend to be bonded in place, and the vibration is restricted to their fixed place. For gases, molecules tend to be free to move in free paths. This means that when heated gases are more likely to diffuse faster when compared to solids, and in measuring the internal energy possessed by the heated gas, a thermometer such as bimetallic strips and thermostats can be used. Commonly used scales to understand the temperature level include; Kelvin, Celsius, and Fahrenheit. Interestingly, all these scales can be converted from one to the other through the use of special formulas, as shown below.

=……………..(i) Changing Celsius to Fahrenheit

= (-32)…………….. (ii) Changing Fahrenheit to Celsius

=+273……………….. (iii) Changing Celsius to Kelvin

The idea supporting thermodynamics is that the system will revert to its original equilibrium condition. The laws of thermodynamics make it obvious that heat energy is necessary for the world to reach its final equilibrium.