Complex Frequency and the Laplace Transform
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Questions
In the context of complex frequency, represented as s = σ + jω, what do the real part (σ) and the imaginary part (ω) represent?
View answer and explanationWhat are the complex frequencies present in the time-domain function f(t) = 5e^(-7t) cos(80t)?
View answer and explanationWhat is the one-sided Laplace transform, F(s), of the unit-impulse function, f(t) = δ(t)?
View answer and explanationThe Laplace transform of a current is I(s) = 5/(s+3). If the initial current i(0-) is 2 A, what is the Laplace transform of its derivative, di/dt?
View answer and explanationUsing the initial-value theorem, find the value of f(0+) for the function whose Laplace transform is F(s) = (3s + 12)/(s^2 + 2s + 10).
View answer and explanationWhat is the key condition for applying the final-value theorem to a Laplace transform F(s)?
View answer and explanationWhat is the inverse Laplace transform of the function G(s) = (7/s) - 31/(s + 17)?
View answer and explanationWhat is the result of applying the initial-value theorem to the transform V(s) = (1/s) + 8/(s+4)?
View answer and explanationWhat is the Laplace transform of the time function f(t) = te^(-αt)u(t)?
View answer and explanationThe sifting property of the unit-impulse function is demonstrated by which integral expression?
View answer and explanationIf a function in the time domain, f(t)u(t), is delayed by 'a' seconds, resulting in f(t-a)u(t-a), how does its Laplace transform F(s) change?
View answer and explanationA function has a Laplace transform F(s) = (2s+4)/s. What is the correct inverse Laplace transform f(t)?
View answer and explanationWhat is the complex frequency of a DC voltage V0?
View answer and explanationIn the series RLC circuit from Example 14.1 with R=2 ohms, L=3 H, and C=0.1 F, what is the complex current I if the forcing function is V = 60 at angle 10 degrees and the complex frequency is s = -2 + j4?
View answer and explanationWhat is the Laplace transform of the function f(t) = 2u(t - 3)?
View answer and explanationWhat is the purpose of the one-sided Laplace transform in circuit analysis?
View answer and explanationWhat is the inverse Laplace transform of F(s) = 1/((s + α)(s + β))?
View answer and explanationHow is the Laplace transform of the integral of a function, ∫f(x)dx from 0- to t, related to the function's transform F(s)?
View answer and explanationWhat is the inverse Laplace transform of the function P(s) = (7s + 5) / (s^2 + s)?
View answer and explanationFor the series RL circuit in Example 14.7 with R=4 ohms, L=2 H, and an initial current i(0-)=5 A, what is the complete expression for the current i(t) for t > 0 when a 3u(t) V source is applied?
View answer and explanationWhat is the Laplace transform of cos(ωt)u(t)?
View answer and explanationUsing the final-value theorem, determine f(infinity) for the transform F(s) = 10 / (s^2 + 3s).
View answer and explanationIf you are given a Laplace transform F(s) where the degree of the numerator is equal to the degree of the denominator, what is the first step in finding the inverse transform?
View answer and explanationIn the context of the Laplace transform, what does the linearity theorem state?
View answer and explanationFind the inverse Laplace transform of V(s) = 2 / (s(s + 6)^2).
View answer and explanationWhat is the physical interpretation of a complex frequency s having a positive real part (σ > 0)?
View answer and explanationWhat does the Laplace transform pair f(t) <=> F(s) establish between the time domain and the frequency domain?
View answer and explanationGiven a function g(t) = 3[e^(-t) - te^(-2t) - e^(-2t)]u(t), what is its Laplace transform G(s)?
View answer and explanationWhat is the Laplace transform of the rectangular pulse defined by v(t) = u(t-2) - u(t-5)?
View answer and explanationWhich property or theorem is most directly used to transform a linear integrodifferential circuit equation from the time domain into an algebraic equation in the s-domain?
View answer and explanationWhat is the final value, f(infinity), for a function whose Laplace transform is F(s) = (s^2 + 6)/(s^2 + 7)?
View answer and explanationA function is defined as f(t) = 2 - 4t + 3.5te^(-10t). What is its Laplace transform H(s)?
View answer and explanationWhat are the values of the residues 'a' and 'b' for the partial fraction expansion of P(s) = (7s + 5) / (s(s + 1)) = a/s + b/(s+1)?
View answer and explanationThe Laplace transform of a function is given as I(s) = (0.75/s) + (4.25/(s+2)). What is the value of the function i(t) as t approaches infinity?
View answer and explanationWhat is the general form of a real time function that has frequency components at s = -5, s = j8, and s = -j8?
View answer and explanationThe time-domain function for a series RC circuit is u(t) = 4i(t) + v(0-) + 16 ∫i(t')dt' from 0- to t. What is the corresponding s-domain equation?
View answer and explanationHow are the poles of a rational function F(s) = N(s)/D(s) defined?
View answer and explanationGiven H(s) = (2/s) - (4/s^2) + 3.5/((s+10)(s+10)), what is the corresponding time-domain function h(t)?
View answer and explanationIf a function f(t) is multiplied by e^(-at) in the time domain, how does its Laplace transform F(s) change?
View answer and explanationThe Laplace transform of a ramp function, tu(t), is 1/s^2. Using the frequency-shift theorem, what is the transform of f(t) = 5te^(-3t)u(t)?
View answer and explanationWhat is the initial value i(0-) of the current in the RL circuit of Example 14.7, as required to solve the problem?
View answer and explanationA Laplace transform is given by F(s) = 4e^(-2s)(s+50)/s. What is its initial value, f(0+)?
View answer and explanationThe function q(t) has a Laplace transform Q(s) = (11s + 30) / (s^2 + 3s). What is q(t)?
View answer and explanationWhat is the result of using the sifting property to evaluate the integral of 4t^2 * δ(t - 1.5) dt from negative to positive infinity?
View answer and explanationA function V(s) has a simple pole at s = -a, a simple pole at s = -b, and no other poles or zeros. To find its inverse transform v(t), what is the first step in the method of residues?
View answer and explanationWhat type of time-domain function corresponds to a Laplace transform with a repeated pole at s=-α, such as F(s) = K/(s+α)^2?
View answer and explanationFor a circuit problem involving a capacitor with an initial voltage v(0-), how is this initial condition incorporated into the s-domain equations using the time integration theorem?
View answer and explanationGiven the function Q(s) = (3s^2 - 4)/s^2, what is the inverse transform q(t)?
View answer and explanationThe Laplace transform for the derivative of a function is given as s^2 * V(s) - s*v(0-) - v'(0-). What derivative is being transformed?
View answer and explanationA time function is given by the expression (u(t) - e^(-10t))u(t). What is its Laplace transform V(s)?
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