Recent content by asitiaf

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    Second shifting theorem of laplace transform

    My question is why do we use unit time shifted step function? I never said f is defined between zero and infinity. f can also have t- values. Then f(t-a) does not mean f is defined between a and infinity. f(t-a) just means, f(t) shifted by "a" time, where "a" can be negative, positive or...
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    Second shifting theorem of laplace transform

    1. why do we need to use shifted unit step function in defining second shifting theorem? 2. why don't we instead calculate laplace transform of a time shifted function just by replacing t by t-a? 3. everywhere in the books as well as internet i see second shifting theorem defined for...
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    Why cosine wave for phase deviation in phase modulation?

    Phase modulation is a system in which the amplitude of the modulated carrier is kept constant, while its phase and rate of phase change are varied by the modulating signal. By the definition of phase modulation, the amount by which the carrier phase is varied from its unmodulated value, called...
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    Orbital Hybridisation: How Tetragon in sp3 is Formed

    In sp3 hybridisation, how a tetragon is formed? As per book, in ch4 (methane) there are four sigma bond of same length and strength. But we are having three sp sigma bonds (between s of H and p of C) and one ss sigma bond( between s of H and s of C). Then how can sp and ss sigma bond be of same...
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    Engineering drawing - projection of lines

    Homework Statement A line Ab inclined at 30• to the Hp has its ends a and b, 25 mm and 60 mm behind the vp respectively. The length of the top view is 65 mm and its vt is 15 mm below the Hp. Draw the projections of the line and locate its ht. also, determine the true length of the line Ab and...
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    Operation of SCR: Starting Conduction & J2 Breakdown

    When we apply voltage to the gate of an SCR, how does it start conducting? Current passes through gate to cathode. Then how the breakdown of junction j2 occurs?
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    AC Passes Through Inductor: Fact or Fiction?

    DC is blocked by a capacitor But AC passes by a capacitor. Why? If above mentioned logic is taken into account. Taking the frequency consideration how the leading and lagging of current is interrelated.
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    AC Passes Through Inductor: Fact or Fiction?

    While studying electrical science, I was told that when an alternating current passes through an inductor, current lags voltage by 90•. And when through a capacitor, current leads voltage by 90•. But while studying transistors in electronics, I was told that AC passes through a capacitor but...
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    Maintaining Voltage Stability with a Zener Diode

    The diode will not be conducting if input voltage is less than diode voltage. Vin = (RL+RS)*I Voltage across Rs = Rs*I Suppose, first case Vz = 5V Vin = 4V Rs = 2ohm RL = 6ohm Now, I = 0.5 A Voltage across Rs = 0.5*2 = 1V And voltage across RL = 0.5*6 = 3V Second case, Vin = 5V Rest all same...
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    Maintaining Voltage Stability with a Zener Diode

    I understand that excess voltage will be dropped across Rs, when input voltage is greater than Zener voltage. But I'm asking will there be any current through RL, if input voltage is less than Zener voltage. Give reasons for the answer.
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    Maintaining Voltage Stability with a Zener Diode

    I'm rather confused about Zener diode. Can someone explain in detail about it. As per my opinion when the input voltage is less than Zener diode, the diode acts like an open switch and no current flow through the circuit. But while I'm using it as a voltage regulator, we connect the load across...
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    Maintaining Voltage Stability with a Zener Diode

    How do Zener diode keep voltage constant if input voltage is less than Zener voltage
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    Integration question (average voltage)

    what is wrong if you integrate the functions in the limit specified?
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