Snells Law, Refraction And Reflection Of Ultrasonic Waves

Like light, when an incident ultrasonic wave encounters an interface to an adjacent material of a different velocity, at an angle other than normal to the surface, then both reflected and refracted waves are produced.

Understanding refraction and how ultrasonic energy is refracted is especially important when using angle probes or the immersion technique. It is also the foundation formula behind the calculations used to determine a materials first and second critical angles.

First Critical Angle

Before the angle of incidence reaches the first critical angle, both longitudinal and shear waves exist in the part being inspected. The first critical angle is said to have been reached when the longitudinal wave no longer exists within the part, that is, when the longitudinal wave is refracted to greater or equal than 90, leaving only a shear wave remaining in the part.

Second Critical Angle

The second critical angle occurs when the angle of incidence is at such an angle that the remaing shear wave within the part is refracted out of the part. At this angle, when the refracted shear wave is at 90 a surface wave is created on the part surface


The relationship between the angle of the incident and refracted sound waves is descibed by the following formula:

Sin(A1)/V1 = Sin(A2)/V2


A1 = The incident sound wave angle in degrees
V1 = The acoustic velocity of the incident material in metres per second
A2 = The refracted sound wave angle in degrees
V2 = The acoustic velocity of the refracted material in metres per second

By simple arrangment the formula may be changed to find any one of the values, provided that the other three unknown values are supplied.

E.g. To find the refracted angle, given the incident angle and velocity and the refracted material velocity the equation is rearranged as below:

V2 * (Sin(A1)/V1) = Sin(A2)

Getting the inverse of the answer, that is the inverse of Sin(A2) will return the angle in degrees of the refracted angle.

If this all seems a bit too hard, but your desperate for an instant answer then visit for the free online calculator!

What is the Law of Reciprocity

I have just read a book called The 10 Keys to Create Wealth to fulfill your lifes purposes. I paid special attention to the chapter talking about The Law of Reciprocity. I kept thinking; what does that mean? It is simply this: If you want to prosper in all areas of your life then you must give back to the community by offering a valued benefit for those you around you.
Ok, what does she mean? What I mean is this. If you want to succeed in life you have to give back. It is the unwritten law of nature. God speaks of this in his word. Give and it will be given unto you, good measure, pressed down and running over, will be poured into your lap. For with the measure you use, it will be measured to you
Let me give you some examples:
A man I would like to meet, but have not yet is Michael Ellison who is the author of The 10 Keys to Create Wealth to fulfill your lifes purpose, is the classic example of a man using The Law of Reciprocity . He has achieved greatness in his family, friends, wealth and health by using this formula. He believes that by offering a wellness program to the community and by serving God at the same time he is giving something of value that benefits his clients. We all want to be healthy and gain financial wealth, dont we? I know I do. Now my thought is; how do we achieve this? For what gain is there to have wealth and no health. What do you profit if you spend your days wealthy and sick and no one to share your wealth with?
**Give something of Value and let it be a benefit to mankind**
Wealth is what you determine it to be. Some call it money in the bank, others call it having family, friends, a relationship with God, etc I say it can be that but can also include the wealth of prospering others in all walks of life by being a blessing to them and solving a problem for them.
If you were walking down the street and found a man injured on the road would you take the time to help him? The fact is that in this day and age most of us would call 911 or the police. The Law of Reciprocity is a different approach. Go to the injured man and assess his condition, talk to him to bring him comfort and to let him know you are there to help him, call the appropriate help, stay with him until help arrives, ask him if you can pray with him or if there is another way you can help him. Call his family, his friend or clergy. Do you see the difference here? You gave him something of value. It was not monetarily given but given from a human aspect. You put yourself out there. Now in 5 years when he tells this story to his friends or family do you think he will remember your kindness? Will he remember you? What will his thought be? I think it will be something like this.You know, I will never forget how sweet she was to help me and comfort me, she even offered to call people for me and to pray with me. Do you see here how that will stay with that person? You can do it the easy way, but will they remember? Most definitely not!
I would recommend this book to anyone for this chapter all by itself however there are many golden nuggets through out the entire book. I am glad you took the time to read my article and let me leave you this final thought.
We determine and choose in life our success and our failure. What will your choice be? Mine will be success in every aspect of my life by applying The Law of Reciprocity!
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May God bless you and keep you!

Employment Law Attorneys Help Resolving Your Workplace Issues In A Legal Manner

Every country has its own law of employment that can differ from others. For instance, the laws of UK will never be the same as that of, Switzerland. These laws are also known as labor laws as these laws are amended for the protection of employment interests or workforce. Employees are less potent and poorer class than the employer, who is considered much stronger and richer in the both. Such laws are constructed to provide fair justice to both the parties because complexities might influence any of the party. In such situations, the employment law attorneys play a very imperative role. They help both parties to understand the significance of legal terminologies.

Whenever you feel harassed at your workplace or your rights are denied in the official setup, then seeking help from lawyers would be a great idea. But make sure that you are hiring a lawyer who has gained an expertise in practicing employment laws. These lawyers will serve you as the guardians of law and protect your rights. They work cooperatively to provide clear understanding of your legal rights by offering best options. The law of employment is itself a wide arena, which comprises of all kinds of legal requirements and guidelines that should never be violated.

In case you are having issues at your workplace then there comes the need of an employment lawyer. Some situations in which you might need some legal assistance are: termination of employment, discrimination, mistreatment, etc. For example, if your employer wants to terminate your employment due to a substantial drop in performance that you are not able to improve, reaching out to attorney in such case would be highly recommended. It doesn’t matter what legal reason your employer gives, it is your duty to discuss about it with your lawyer. He will assure that the entire process is carried in a legal manner as per labor and employment law without resulting into any kind of negative influences on you.

You can face numerous employment law issues at your workplace. You might not be treated well or treated in an illegal manner. It can be in any form including unfair dismissal, contracts complications, or any other issues. A good attorney will give the best advice for resolving such issues. Even the employment discrimination issues are pretty common now-a-days. It can be either due to age, skin color, religion, gender, physical appearance, sexuality, nationality etc. And the discrimination at workplace could result into prejudice, racial tension and a stressed work environment. It is not at all a favorable situation and can negatively impact a person’s job, career as well as his or her personal life. The lawyers examine each issue carefully and help you to decide whether you should move forward for a court case or not.

Fight for your rights if you have been treated in a wrong manner since a long period of time. Seek help from attorneys who will educate you about your rights and responsibilities. If you are facing any issues like racial slurs, improper conduct or comments towards you, it is your duty to discuss your problems with the attorney if you want proper justice.

Definition And Use Of Tort Law

Simply put torts are civil laws that recognize personal wrongs which answer to a charge of law as grounds for accountability or lawsuit. These are wrongs that have resulted in personal injury or harm and are grounds for seeking a claim of compensation by the injured party. Some torts are civil crimes which are punishable by imprisonment but the main reason of tort law is to provide a way to be compensated or get relief for damages inflected and to discourage any one else from committing the same harmful violations. The person who was injured may sue for an injunction to halt the damaging conduct or for monetary compensation for damages encountered.

There are several types of damages an injured party may make claim and receive compensation from, such as : loss of wage capacity, pain and suffering, undue mental duress, and reasonable medical expenses. Claims can include both present and future expected losses. Included amongst the most common of torts are: trespass, assault, battery, negligence, product liability, and intentional infliction of emotional distress (harassment).

Torts also fall into three general categories:

1.intentional torts (e.g., intentionally harming a person);

2.negligent torts (causing an accident by failing to obey traffic rules); and

3.strict liability torts(e.g., liability for knowingly making and selling defective products

Intentional torts are those wrongs which the defendant had knowledge of, or by reason should have known, would occur through their direct involvement, being a part of or intentional lack of action. Negligent torts are when the defendant’s actions are deemed unreasonably unsafe. Strict liability wrongs don’t depend on how little the defendant’s sense of responsibility was, but is established after the fact, when a particular action causes damage. A person may operate in a unreasonable manner but is not subject to tort until a claim to cease and desist or call for compensation is made.

Tort law is derived through common law Judges and enacted into state law by legislatures which enact statutory law.

General Principle Torts (1) Any one who invades the privacy rights of another is subject to liability payment for any resulting damage to the interests of the person who was harmed. Privacy invasion is explained by: (a) unreasonable intrusion upon the seclusion of another, or (b) identity theft, appropriation of the other’s name or likeness, or (c) Malicious, false or unreasonable publicity given to other person’s private life, or (d) publicity of an unreasonably nature that places the other person in a false light before the public, Intrusion upon Seclusion is a person who intentionally intrudes, physically or otherwise, upon the solitude or seclusion of another person or his/her private affairs or concerns. The wrong doer is subject to liability to the wronged for invasion of privacy, if the intrusion is seen as highly offensive to a reasonable person. Appropriation of Name or Likeness (identity theft) is a person who takes the name or likeness of another for his/her own use or benefit The wrong doer is subject to compensate the wronged person for invasion of privacy.

Get the Right Injury Law Firm in St. Petersburg

In recent years there has been an increase in the amount of cases that have needed representation. Among the most numerous of these cases are those in which someone was injured and a settlement needs to be made. While this can be a sticky situation there are ways to save the stress and difficulties that come with such circumstances. There are some tips that, if followed, will make finding the right injury law firm in St. Petersburg as easy as possible.

Before you begin your search for the right injury law firm in St. Petersburg you will want to make a specific and detailed outline of your situation. The more detailed and specific that you are to the law firm it will allow them to give you the adequate assistance you require. This will not only help your law firm to provide as much assistance as they can but it will also help you to get clear on what exactly it is that happened. There is something in writing down on paper what happened that helps clear up any uncertainties that you might have in what exactly it is that happened. With this clear and detailed outline you will then be able to accurately explain to your injury law firm in St. Petersburg what happened and then they will be able to explain exactly what they can do to be of service to you.

After making a detailed outline it is now time to find the right law firm to represent you and your case. While there are many different firms to choose from there are ways to find the right one. Using your outline you can narrow down your choices by finding that firm that specializes in whatever you case might be. There are firms that specialize in automobile injuries and others that specialize in domestic abuse. You will want to find the injury law firm in St. Petersburg that has a proven history in representing others that were in your situation. This will give you the best chance of getting all you can out of the case.

After narrowing down your search it is time to find the right injury law firm in St. Petersburg to represent you and your case. With the narrowed search you will want to find the one that you feel has the best chance of winning your case. Finding the one with a proven history of representing people that were in the same situation as you is a great place to start. That will show to you that they know what they’re doing and you can feel comfortable entrusting them with your case.

While finding the right injury law firm in St. Petersburg can seem like a difficult and sometimes daunting task, following these simple tips will help make it as easy as anything. By making a simple outline, narrowing down your search and finding those that have a proven history in cases such as yours, you will be giving yourself the best opportunity of success and you will have comfort entrusting them with your case.

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