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The waveform shown in a sweep voltage used to defect the beam in a cathode ray oscilloscope. The transform of this function can be written as—
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F (s) = 1 - e–as as2 s(1 – e–as) -
F (s) = 1 - e–as as s(1 – e–as) -
F (s) = 1 - eas as2 s(1 – e–as) -
F (s) = 1 - e–as as2 s(1 + e–as)
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Correct Option: A
In order to calculate the L.T. of periodic saw took waveform use the relation given below.
F(s) = | |
1 −e−Ts |
where F1(s) = Laplace transform of the single waveform
T = Time period of the given wave
Calculation for F1(s)
F1(t) = | t r (t) − | (t − a) r (t − a) − 1 u (t − a).....(i) | ||
a | a |
taking Laplace transform both side, we get
F1(s) = | − | − | e−as | ||||
as2 | a | s2 | s |
Time period (T) = a
Now F(s) = | |
1 − e−Ts |

or
F(s) = | − | ![]() | ![]() | |||
as2 | s | s | ||||
1 − e−as |
or F(s) = | − | ||
as 2 | s (1 − e−as) |