The rst derivative function time becomes and kdv becomes ksv
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2. A constant k which does not vary with time remains a constant. Thus kv , where v is a function of time, becomes kV(s). For example, the voltage 3 v written as an s function is 3 V(s).
3. If the initial value of the variable v is zero at time t� 0, the fi rst derivative of a function of time dv/dt becomes sV(s) and kdv/dt becomes ksV(s). For example, with no initial values 4dv/dt as an s function is 4sV(s).
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Control and Instrumentation Systems |
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With an integral of a function of time:
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v | d becomes | 1 s V s ( ) |
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kv | d becomes |
into an s function.
Example 18.14
v | � | � |
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Solution
V s ( ) | � | RCsV C | ( ) | � |
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V C( )� | 1 | ||
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RCs | � | 1 |
The above equation thus describes the relationship between the input and output of the
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