Laplace Transformation

Laplace Transform

What is Laplace Transformation?

Laplace transform, is an integral transform that converts a function of a real variable, usually time, to a function of a complex variable or complex frequency. It is named after a great French mathematician, Pierre Simon De Laplace. It changes one signal into another based on some fixed set of rules and equations. It is considered the best way to convert an ordinary differential equation into algebraic equations and convolution into multiplication which aids in solving them faster and in a significantly easier approach.

Laplace transform is considered a generalized Fourier series. This is done so as to allow us to obtain multiple transforms of any function that does not have Fourier transforms. This concept is used in a lot of domains. Also, it is essential to have a complete understanding of the concept if you are working on mathematical concepts. It holds a significant role in control system engineering. To analyze control systems, different functions will be carried out. Both the Laplace transform and the inverse Laplace transform are used to analyze the dynamic control system. This transform has its applications in various applications in different types of science and engineering since it is a tool used to solve differential equations. 

A function is considered piecewise continuous if it has a finite number of breaks and if it does not go into infinity at any point. If f(t) is considered a piecewise continuous function, then f(t) is defined using this approach. It is represented by L{f(t)} or F(s).

Laplace Transform Table:

Laplace transform simplifies a differential equation into a simple algebraic expression. The laplace transform table is available to engineer data on the Laplace transforms. 

Properties:

Below listed are the important properties of Laplace transform:

• Linearity: L {C1 f(t) + C2 g(t)} = C1 L{f(t)} + C2 L{g(t)}

Where C1, C2 are constants; f(t) is the function of time t.

• First shifting theorem

• Change of scale property

• Differentiation

• Integration

• Time shifting

• The final value theorem is applicable in the analysis and design of feedback control systems since Laplace transform gives a solution at initial conditions.

• Initial value theorem

Application of Laplace Transform:

Laplace transform is a derivation of Lerch’s Cancellation Law. In this transformation method, the function in the time domain is transformed into a Laplace function in the frequency domain. This function will be in the form of an algebraic equation, which can be solved quickly. The obtained solution can be transformed back again into the time domain by using the inverse Laplace transform method.

Laplace transform is most commonly used for control systems, and it is used to study and analyze systems such as ventilation, heating, air conditioning, etc. All of these are used in all modern-day construction and building.

Laplace transforms to make a significant contribution to process controls. It helps in performing variable analyses that produce the required results when altered. Conducting experiments with heat can be registered as an example of this.

Laplace transform is also applied in many other engineering domains like mechanical engineering and electronic engineering, and this proves to be a powerful method. 

A differential equation can represent the control action for a dynamic control system, be it mechanical, electrical, hydraulic, thermal, etc. The differential equation of a system is derived according to physical laws that govern a system. The differential equation is transformed into an algebraic equation to help facilitate the solution of a differential equation describing a control system. This kind of transformation is achieved with the help of the Laplace transformation technique. This means the time domain differential equation is converted into a frequency domain algebraic equation form.

A fascinating analogy that will help understand Laplace is an example from English literature. Let’s say you come across an English poem that you cannot grasp. Fortunately, you have a French friend who is good at making sense of this poem. All you have to do is, translate this poem you don’t understand into French and send it to your friend, considering you are good at French. Your friend will then explain the literature behind this poem and send it back to you. You understand the French explanation and then transform it into English and hence understand the English poetry.

Inverse Laplace Transform:

The inverse Laplace transform is a piecewise continuous and exponentially restricted real function f(t) with the property:

L{f}(s) = L{f(t)}(s) = F(s)

Here, L denotes Laplace transform.

If any function F(s) has an inverse Laplace transform f(t), then f(t) is uniquely determined considering functions that differ from each other only on a point set having Lebesgue measure zero as the same. This is called Lerch’s theorem, and this means there is an inverse transform on the range of transform. 

Inverse Laplace transform has a space of analytical functions in the region of convergence. It is given by complex integrals known by the names Bromwich integral, the Fourier Millin integral, and Mellin’s inverse formula.

Drawback:

Laplace transform is restricted to solving complex differential equations with known constants. If there is a differential equation without known constants, this method is useless, and some other method has to be applied to solve such problems.

This program is designed for individuals who aim to get a thorough understanding of Laplace transform to seek excellence in the field of mathematics and other sciences. This will help college students crack real-time problems significantly easier and faster. This course will cover all the parts of Laplace transform and also guide its subscribers to crack through a few example problems. This will also confer the information on inverse Laplace transformation, Laplace transform table, and more. While you learn about Laplace transform, you will increase your comprehension of its essentials. You will be acquainted with most of its applications and apply them to solve other such problems.

This particular course is 1 hour long, where you will be gaining knowledge on different methods used to crack through the approach and various other related objectives. 

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