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Unit Impulse Function

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Unit Impulse Function                 The above figure shows a function which has a zero value when t is negative , rises instantaneously to a value 1/t₀ when 0<t<t₀ , and is zero thereafter.                  If we let t₀--> 0 , this function  tends towards infinity as t₀--> 0, but width decreases inversely with the magnitude ; hence area under the curve remains finite . The unit impulse function is represented by δ(t) .  Among Physicists, the unit impulse function is referred to as the 'Dirac δ-function ' after the name of great Physicist Dirac , who is the first to use this function in systematic manner .  The Dirac δ - function at the point t=a as in above figure is represented by δ(t-a) . Thus                       {0 for t < a         δ(t-a) ={ 1/t₀ for a<t<a+t₀                       {0 for t> a+t₀              .......(1) Where t₀ --> 0 in the limit .       The Laplace transform of δ(t-a) is