Physical Intuition
Intuitively, the theorem simply states that the sum of infinitesimal changes in a quantity over time (or over some other quantity) adds up to the net change in the quantity.
In the case of a particle traveling in a straight line, its position, x, is given by x(t) where t is time and x(t) means that x is a function of t. The derivative of this function is equal to the infinitesimal change in quantity, dx, per infinitesimal change in time, dt (of course, the derivative itself is dependent on time). This change in displacement per change in time is the velocity v of the particle. In Leibniz's notation:
Rearranging this equation, it follows that:
By the logic above, a change in x (or Δx) is the sum of the infinitesimal changes dx. It is also equal to the sum of the infinitesimal products of the derivative and time. This infinite summation is integration; hence, the integration operation allows the recovery of the original function from its derivative. It can be concluded that this operation works in reverse; the result of the integral can be differentiated to recover the original function.
Read more about this topic: Fundamental Theorem Of Calculus
Famous quotes containing the word physical:
“... life is moral responsibility. Life is several other things, we do not deny. It is beauty, it is joy, it is tragedy, it is comedy, it is psychical and physical pleasure, it is the interplay of a thousand rude or delicate motions and emotions, it is the grimmest and the merriest motley of phantasmagoria that could appeal to the gravest or the maddest brush ever put to palette; but it is steadily and sturdily and always moral responsibility.”
—Elizabeth Stuart Phelps (1844–1911)