Calculate Energy of Signal x(t) = e(-2t) * u(t)

In summary, the formula for calculating the energy of a signal is E = ∫x(t)^2 dt, where x(t) represents the signal and the integral is taken over the entire time domain. For a signal with a time-dependent amplitude, the energy can be calculated by first finding the squared magnitude of the signal at each time point, and then integrating this over the entire time domain. "e" represents the mathematical constant known as Euler's number, which is approximately equal to 2.71828, and is often used to model exponential growth and decay in signal analysis. The unit step function u(t) serves as a switch that turns the signal on at t = 0 and keeps it off for all negative values of t,
  • #1
drkidd22
59
0

Homework Statement



x(t) = e(-2t) * u(t)

Ex = x2(t) dt

Attached is the work I have done. Got stuck towards the end.
 

Attachments

  • #2.bmp
    285 KB · Views: 522
Physics news on Phys.org
  • #2
[tex](e^{-2x})^2 = e^{-2x}e^{-2x}=e^{-2x-2x}=e^{-4x}[/tex]
or you can use the power property associated with exponents and instantly say
[tex](e^{-2x})^2=e^{2(-2x)}=e^{-4x}[/tex]
I'm assuming the exponential being squared is what messed you up, and I'm assuming you can take it from here.
 

FAQ: Calculate Energy of Signal x(t) = e(-2t) * u(t)

What is the formula for calculating the energy of a signal?

The formula for calculating the energy of a signal is E = ∫x(t)^2 dt, where x(t) represents the signal and the integral is taken over the entire time domain.

How do you calculate the energy of a signal with a time-dependent amplitude?

For a signal with a time-dependent amplitude, the energy can be calculated by first finding the squared magnitude of the signal at each time point, and then integrating this over the entire time domain. In other words, the formula becomes E = ∫|x(t)|^2 dt.

In the given signal x(t) = e(-2t) * u(t), what does "e" represent and what is its significance?

In this signal, "e" represents the mathematical constant known as Euler's number, which is approximately equal to 2.71828. The significance of "e" is that it is often used to model exponential growth and decay, making it a useful tool in signal analysis.

What is the role of the unit step function u(t) in the signal x(t) = e(-2t) * u(t)?

The unit step function u(t) serves as a switch that turns the signal on at t = 0 and keeps it off for all negative values of t. This ensures that the signal only exists and has a non-zero value for t ≥ 0, making it a causal signal.

Can the energy of a signal ever be negative?

No, the energy of a signal can never be negative. This is because the energy is calculated by squaring the magnitude of the signal, which will always result in a positive value. In addition, physical signals cannot have negative energy, as it would violate the law of conservation of energy.

Similar threads

Replies
2
Views
1K
Replies
4
Views
2K
Replies
4
Views
1K
Replies
6
Views
4K
Replies
1
Views
1K
Replies
7
Views
2K
Replies
67
Views
8K
Replies
1
Views
1K
Replies
7
Views
1K
Back
Top