-
In Laplace transform the variable ‘s’ equal (σ + jω). Which of the following represent the true nature of σ?
1. σ has a damping effect.
2. σ is responsible for convergence of internal ∫∞0 f(t) e– st dt.
3. σ has a value less than zero. Select the correct answer using the codes given below—
-
- 1, 2 and 3
- 1 and 2
- 2 and 3
- 1 and 3
Correct Option: B
We know that s = σ + jω where, σ is known as damping coefficient and
L {f(t)} = ∫∞0 f(t) e– st dt
can be expressed as
L {f(t)} = ∫∞0 f(t) e– (σ + jω)t dt
= ∫∞0 f(t) e– σt e– jωt dt
Here factor e– σt factor is called convergence factor.
Hence alternative (B) is the correct answer.
