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Sharpen Your General Knowledge
Shamim Ansary:
What Causes One Person to Feel Hot While Another Feels Cold at the Same Room Temperature?
It is a complex question, made even more complex by factors like the prior activity of each individual and how long each has been in the room.
Assuming that both people have become acclimatized to the room and that neither is running a fever, there are two important factors.
One is the percentage of body fat, with the higher percentage retaining more heat.
The other is the surface-to-mass ratio for each body, with the larger skin area radiating more heat.
If the room temperature is below the thermoneutral zone, so that the bodies are losing heat to the environment, the person with the larger surface-to-mass ratio feels cooler.
If it were possible to obtain a population of women with exactly the same percentage of body fat as a population of men, the women would feel colder, because they have a larger surface-to-mass ratio.
If a person is running a fever, the phase of the fever determines whether he feels hot or cold.
In the rising phase of a fever, for example, the person feels cold, and the peripheral blood vessels are constricted in an attempt to retain heat and raise the body temperature.
Shamim Ansary:
How Were Nuclear Weapons Invented and When?
When the first atomic bomb was dropped in 1945 it changed the world for ever. Many people wish it had never been invented at all.
Splitting the Atom. The idea for a weapon made from atomic energy had been around since Albert Einstein came up with his equation E = MC2 (which means there’s an awful lot of energy in absolutely everything, inside atoms). During the Second World War, when many countries were carrying out bombing campaigns on one another, the race was on to find a bomb that used the power of atoms.
Getting at the energy inside atoms isn’t easy: for that you have to split them (this is called nuclear fission). Atoms are the tiny units of matter everything is made of and they are a million times smaller than the width of one of the hairs on your head. So you can imagine how tricky it is to split one.
The top secret Manhattan Project in America gathered together some of the brainiest scientists in the world to try and manage it. Eventually, they succeeded. In 1945 two fission (or atomic) bombs were dropped on the Japanese cities of Nagasaki and Hiroshima, killing more than 200,000 people. Some people argue that the bombs saved lives because they ended the Second World War.
Nuclear fusion was developed soon after. This new way of releasing atomic power produces weapons hundreds of times more powerful than atomic bombs. They’ve never been used in warfare. Let’s hope they never will be.
Which year saw the first ever use of a nuclear weapon in military action?
How many people are estimated to have died from the nuclear bomb dropped on Hiroshima and its after-effects?
How does a nuclear fusion explosion work?
How many nuclear weapons have been used in military action?
How does a nuclear fission explosion work?
What does A-bomb stand for?
What type of climate is predicted if there were to be a nuclear war?
Apart from in nuclear weapons, where else can you find radiation?
Shamim Ansary:
What Do Real Estate Lawyers Actually Do?
For most of the country the actual sales contract or offer is a formdocument approved by the National Association of REALTORS® that contains all required legal language, so attorneys are not consulted until after the document is signed. In most states there are laws that allow an attorney a short period of time (an average of three to five days) to review the sales contract or offer made by the buyer and accepted by the seller. A real estate attorney begins looking out for the well-being of his or her client with the first review of this document. At that stage, the attorney makes sure the contract reflects the intentions of his or her client.
The next step for the attorney may be to order the home inspection that the buyer has made contingent in the sales contract. Once the inspection report is complete, the attorney will review the report and alert the buyer to any potential issues with the structure of the house. The attorney may then assist the buyer in negotiating a reduction in price, a cash settlement, or a cancellation of the deal due to the inspection results.
The attorney will advise his or her client as to options for holding the title to the property. Depending on local custom, the attorney will order a title search from a title insurance company and a professional survey. The title search verifies that the sellers have a clear title to the home. The attorney reviews this search and alerts both buyer and seller of any potential problems. For example, the problem may be a lien on the home by a former contractor that was not paid. Knowledge of this issue at an early date allows the seller to resolve the debt before closing. The title insurance company also issues an insurance policy on the title guaranteeing that the buyer has a clear title or the insurance company pays. In many parts of the country the title insurance company also provides a closing agent and an office where the closing can take place. The survey is a certified drawing of the land, how the house and other structures sit on the land, including actual measurements.
As the closing gets closer, the real estate attorney will monitor the progress and review documents. The attorney will assist the closing agent in drafting the list of closing costs and, once that draft is completed, review the calculations. When it comes time for the closing, the real estate attorney stands with the buyer. The attorney reviews each document and lets the buyer know what he or she is signing. If problems come up in the closing, the real estate attorney may be able to resolve the problems on the spot. An experienced real estate attorney advocates for the client and protects the client from being taken advantage of in this deal.
Shamim Ansary:
Why Is Uranium Used In Atomic Bombs?
Uranium is used in atomic weapons and in nuclear power plants because it is a radioactive element. The atoms of a radioactive element break down over a period of time, losing particles from their nucleus and releasing energy.
Normally, this breakdown happens in only a few uranium atoms at a time. But in an atomic bomb, the atoms break down very quickly, releasing great amounts of energy all at once.
Uranium atoms break down inside an atomic bomb because they’re hit with nuclear particles called neutrons. When a neutron strikes the nucleus of an uranium atom, it causes the nucleus to split apart.
This releases energy and sends particles from the uranium atom crashing into other atoms, which then split, sending out more energy and particles, and so on. This process is called a
chain reaction.
Once the chain reaction inside the atomic bomb’s uranium begins, it keeps going until most of the atoms have been split. This happens in a fraction of a second, so that all the uranium’s energy is released at once.
The breakdown of the atoms in just one pound of uranium can produce energy equal to the burning of almost three million pounds of coal!
Shamim Ansary:
How Cold Is Absolute Zero and What Is the Highest Temperature Possible In the Universe?
There is no maximum temperature, because there is no limit to the amount of energy you can put into anything.
Absolute zero, minus 273.15 degrees Centigrade, minus 459.67 on the Fahrenheit scale, is theoretically the temperature at which all molecular activity ceases.
It represents an absence of energy.
There is the concept of a lowest temperature because any given body has a lowest energy state, when all possible energy has been extracted.
You can also talk about a maximum temperature for any given body, because at some point it will be hot enough to break up, melt or disassociate, so that at that point it would not be the same body.
However, since there will always be some object or substance that will still exist, the concept of temperature does not have an upper limit, because more and more energy could still be added.
A cosmologist might say that this question is like asking “What is the shortest time?â€
Things have been cooling since the big bang, so a millionth of a second later, approximately as far back as our physics will take us now, would theoretically be the hottest known temperature, but a billionth of a second after the big bang would be still hotter.
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