Energy, heat, and temperature all play an important part in the study of the sciences. Some students may have an idea of what these terms mean, but have a hard time explaining them. In order to fully understand chemistry, physics, and other sciences, a student must learn about the details of each one of these terms. With the help of examples, a student can understand more about the meaning behind each of these terms. The following looks at the definitions of energy, heat, and temperature. Also, there is information about some common units of measurement related to these terms.
Chemical, electrical, thermal, and mechanical are just a few examples of the different types of energy. Furthermore, energy takes different forms. For instance, the sunlight is a form of energy. The foods that we eat contain chemical energy. This sort of energy allows us to accomplish physical and mental activities throughout the day. A quickly flowing river illustrates kinetic energy as it moves at a high rate of speed. In short, energy is all around us.
Heat is defined as the transference of energy from one object to another. Heat transfers from hot to cold objects. Conduction, convection, and radiation are three ways that energy can be transferred. Conduction takes place when heat moves between objects that are touching one another. One simple example of conduction is a person walking with bare feet on a hot sidewalk in the summertime. Some of the heat in the sidewalk is being transferred to the soles of the person's feet. The process of convection involves the up and down movement of gases. When a gas takes on heat and gets warmer it rises. Alternatively, when the gas loses its heat and cools, it falls. A student may want to picture a ceiling fan pulling warm air up and letting cool air fall in an effort to better understand the process of convection. Also, a convection oven offers a clear illustration of the concept. Radiation is the transference of heat by way of electromagnetic waves. The sun heats the earth via electromagnetic waves.
Temperature is the measure of heat in an object or substance. A high temperature indicates a large amount of heat. We deal with various temperatures every day. For instance, most people want to know what the temperature will be outdoors. We can take a person's temperature to see if he or she has a fever. Also, if someone is cooking a turkey, he or she can use a thermometer to gauge the temperature of the meat.
Units of Measurement
There are a few common units of measurement in chemistry and the sciences. One example is the joule. A joule is a measurement of energy. Also, a joule represents a SI (International System of Units) unit of heat. According to the Merriam Webster's Collegiate Dictionary (11th ed.) the definition of a joule is a unit of work or energy that is equal to the work done by a force of one newton acting through a distance of one meter.' The term joule honors nineteenth century English physicist James P. Joule. The scientific symbol of joule is 'J.'
Another example of a unit of measurement is a calorie. A calorie is a measurement of heat energy. Many people relate the word calorie to various items of food. It's true that most foods have calories in them and the calories in foods give people energy. A calorie is a scientific unit of measurement coined in the early nineteenth century by a Nicolas Clement, a French chemist. A unit called the kilocalorie is sometimes used with the word calorie. They mean essentially the same thing. The unit of measurement known as a joule is more commonly used in the realm of science than the word calorie.
A unit of measurement seen in connection with a calorie is the Btu (British thermal unit). For instance, a specific number of calories add up to a particular Btu amount. Btu's are used in the course of measuring a variety of things. All of these units of measurement serve to help scientists gauge amounts of energy.