Tacoma Narrows Bridge (1940) Billah and Scanlan (1991) reported that in fact, many physics textbooks (for example Resnick et al. and Tipler et al.) wrongly explain that the cause of the failure of the Tacoma Narrows bridge was externally forced mechanical resonance. Resonance is the tendency of a system to oscillate at larger amplitudes at certain frequencies, known as the system's natural frequencies. At these frequencies, even relatively small periodic driving forces can produce large amplitude vibrations, because the system stores energy. For example, a child using a swing realizes that if the pushes are properly timed, the swing can move with a very
Negative frequency is just a constant whose amplitude level is a measure of the strength of the original "ω" content. And whatever part of "x"("t") that was at frequency zero is changed to a sinusoid at frequency −"ω". Similarly, all other frequencies are changed to non-zero values. As the interval increases, the contribution of the constant term grows in proportion. But the contributions of the sinusoidal terms only oscillate around zero. So "X"("ω") improves as a relative measure of the amount of frequency "ω" in the function "x"("t"). The Fourier transform of formula_1 produces a non-zero response only at frequency "ω". The