Homework
The next problem(s) addresses the following course learning objective(s):
- Understand forward and inverse Laplace transform.
- Obtain the initial value and final values using Laplace transform.
- Obtain a transfer function using the Laplace transform.
Problem 1
Use the defining integral to
a) find the Laplace transform of cosh βt;
b) find the Laplace transform of sinh βt.
Problem 2
Use the appropriate operational transform from Table 12.2 to find the Laplace transform of each function:
a) t2e-at;
b) d/dt(e-at sinh βt);
c) t cos ωt.
Problem 3
Find f (t) if
F(s) = 6s2 + 26s + 26/((s + 1)(s + 2)(s + 3))
Problem 4
Find f(t) if
F(s) = (10(s2 + 119))/((s + 5)(s2 + lOs + 169))
Problem 5
Find f (t) if
F(s) = 40/(s2 + 4s + 5)2.
Problem 6
Find f (t) if
F(s) = (2s3 + 8s2 + 2s - 4)/(s2 + 5s + 4)
Problem 7
Using the initial- and final-value theorems, find the initial and final values of f(t) given as below:
a). F(s) = (7s2 + 63s + 134)/(s + 3)(s + 4)(s + 5)
b). F(s) = (4s2 +78 +1)/ s(s + 1)2
c). F(s) = 40/(s2 + 4s + 5)2
Problem 8
The switch in the circuit in Fig. P12.30 has been in position a for a long time. At t = 0, the switch moves instantaneously to position b.
a) Derive the integrodifferential equation that governs the behavior of the current i o for t ≥ 0+.
b) Show that
Io(s) = - Idc [s + (1/RC)]/[s2 + (1/RC)s + (1/LC)].