Magnetic Field and Permanent Magnets
Permanent magnets are objects that produce their own persistent magnetic fields. They are made of ferromagnetic materials, such as iron and nickel, that have been magnetized, and they have both a north and a south pole.
Read more about this topic: Magnetic Field
Famous quotes containing the words magnetic, field and/or permanent:
“We are in great haste to construct a magnetic telegraph from Maine to Texas; but Maine and Texas, it may be, have nothing important to communicate.”
—Henry David Thoreau (1817–1862)
“... no young colored person in the United States today can truthfully offer as an excuse for lack of ambition or aspiration that members of his race have accomplished so little, he is discouraged from attempting anything himself. For there is scarcely a field of human endeavor which colored people have been allowed to enter in which there is not at least one worthy representative.”
—Mary Church Terrell (1863–1954)
“A country whose buildings are of wood, can never increase in its improvements to any considerable degree.... Whereas when buildings are of durable materials, every new edifice is an actual and permanent acquisition to the state, adding to its value as well as to its ornament.”
—Thomas Jefferson (1743–1826)