Energy is usually defined as the capacity to do work in the scientific world. Though there are many types of work, in practical terms, work can be quantified to equal “force x distance”.
Brief descriptions of some types of energies that we observe and make use of are:
Radiant energy: energy from the sun, also known as solar energy; solar energy heats the atmosphere and Earth’s surface, stimulates growth of vegetation thru photosynthesis and influences global climate patterns.
Thermal energy is associated with random motion of atoms and molecules and can be measured in terms of heat temperature (generated or lost) and volume size when these molecules interact with each other.
Chemical energy is stored in the structural unit of the substance; in this case, the atom or molecule. When substances participate in a chemical reaction, chemical energy is released, stored or converted to other forms of energy.
Kinetic energy is the energy produced by a body or system that is in motion, initiated by an external force. For example, a small snowball at the top of the hill; when someone pushes the snow ball over the hill, it will roll ever faster down the hill and increase mass as more snow adheres to the snowball. As it goes downhill, it constantly picks up speed due to gravity and increased mass. The energy being created is due to the snowball being in motion.
Potential energy is energy available by virtue of an object’s position. For example, back to our snowball example; the snowball has potential energy do to the fact that is at the top of the hill and with the understanding that force of gravity can cause it to increase speed as it goes downhill. When another outside force, in this case, a person pushing the snowball, the potential energy of the snowball is realized when it is rolling downhill and increases in speed and mass. The potential energy of the snowball could not have been realized if you were at the bottom of the hill where there is not a steep slope.
All these types of energies share a central theory that relates it all together. This theory is known as the law of conservation of energy. This law states that energy is neither lost nor destroyed; it is simply converted to another form of energy. If energy is neither lost nor destroyed, but rather converted to another form of energy, it would suggest that the total quantity of energy in the universe is constant.
Relating this theory to our example of the snowball; the potential energy of the snowball is converted to kinetic energy when it starts rolling down the hill. More snow adhering to the snowball as it is rolling is chemical energy being complied or stored. As the snowball gets bigger, its’ mass and volume increase. Let’s say that the snowball stops at the bottom of the hill; exposed to the sun’s rays, the snowball melts, letting off heated vapor or thermal energy into the atmosphere causing the surrounding temperature to increase as well.