The term free body is usually associated wih the notion of a free body diagram, a pictorial device used by physicists and engineers. In that context, a body is said to be "free" when it is singled out from other bodies for the purposes of dynamic or static analysis. The object does not have to be "free" in the sense of being unforced, and it may or may not be in a state of equilibrium. The object is said to be free in the sense that it has been singled out, identified, as the body of interest.
Famous quotes containing the words free and/or body:
“None who have always been free can understand the terrible fascinating power of the hope of freedom to those who are not free.”
—Pearl S. Buck (1892–1973)
“but as an Eagle
His cloudless thunderbolted on thir heads.
So vertue giv’n for lost,
Deprest, and overthrown, as seem’d,
Like that self-begott’n bird
In the Arabian woods embost,
That no second knows nor third,
And lay e’re while a Holocaust,
From out her ashie womb now teem’d
Revives, reflourishes, then vigorous most
When most unactive deem’d,
And though her body die, her fame survives,
A secular bird ages of lives.”
—John Milton (1608–1674)