Fundamental Forces Of Nature
Science Notes: Fundamental Forces of Nature
All forces in nature may be classified into four types. The gravitational force holds together the universe at large, plus the atmosphere, water, and us to the planet Earth. The electromagnetic force governs atomic level phenomena, binding electrons to atoms, and atoms to one another to form molecules and compounds. The strong nuclear force holds the nucleus together. The fourth force, the weak nuclear force, is responsible for certain types of nuclear reactions and has little bearing on energy sources today.
Table 7 shows the four forces, the property on which each acts, and examples of each force. Gravitation and electromagnetism are the two forces with which we will be primarily concerned, as these are the two forces that operate at the macroscopic level of environmental systems. These also currently form the basis of our most prevalent sources for energy technologies. The strong nuclear force is the strongest of the forces. Nuclear fusion reactions on the surface of the sun are the result of the nuclear strong force.
FORCE
RELEVANT PROPERTY
EXAMPLES
Gravitational
Mass
Weight of object near a planet; force that keeps planets in their orbits around the sun
Electromagnetic
Electric charge
Force that keeps an electron in its orbit around the atomic nucleus; (i.e., attraction or repulsion between a “charged” plastic comb and a strand of hair)
Strong Nuclear
Isotopic spin*
Force that keeps protons and neutrons together in a nucleus
Weak Nuclear
Spin*
Force responsible for certain types of nuclear reactions
Table 7: The four fundamental forces (or, interactions) and the properties on which they act. *Spin and isotopic spin are properties of elementary particles that we will not define here.
Exercise:
Find four “sources” of energy and identify the force responsible for the energy transformation. For example, a hydroelectric
All forces in nature may be classified into four types. The gravitational force holds together the universe at large, plus the atmosphere, water, and us to the planet Earth. The electromagnetic force governs atomic level phenomena, binding electrons to atoms, and atoms to one another to form molecules and compounds. The strong nuclear force holds the nucleus together. The fourth force, the weak nuclear force, is responsible for certain types of nuclear reactions and has little bearing on energy sources today.
Table 7 shows the four forces, the property on which each acts, and examples of each force. Gravitation and electromagnetism are the two forces with which we will be primarily concerned, as these are the two forces that operate at the macroscopic level of environmental systems. These also currently form the basis of our most prevalent sources for energy technologies. The strong nuclear force is the strongest of the forces. Nuclear fusion reactions on the surface of the sun are the result of the nuclear strong force.
FORCE
RELEVANT PROPERTY
EXAMPLES
Gravitational
Mass
Weight of object near a planet; force that keeps planets in their orbits around the sun
Electromagnetic
Electric charge
Force that keeps an electron in its orbit around the atomic nucleus; (i.e., attraction or repulsion between a “charged” plastic comb and a strand of hair)
Strong Nuclear
Isotopic spin*
Force that keeps protons and neutrons together in a nucleus
Weak Nuclear
Spin*
Force responsible for certain types of nuclear reactions
Table 7: The four fundamental forces (or, interactions) and the properties on which they act. *Spin and isotopic spin are properties of elementary particles that we will not define here.
Exercise:
Find four “sources” of energy and identify the force responsible for the energy transformation. For example, a hydroelectric