Is microwaving food safe?

Is microwaving food safe?

There are two aspects to this.  One of them – is food in a microwave dangerous to eat?  The other is, if you go near a microwave, is it dangerous?

First of all, microwaves are a form of light, a form of electromagnetic radiation.  In the spectrum, you go from visible green, yellow, red, into the infrareds, the deep infrareds, through some millimetre waves and then there are microwaves and just beyond that, radio waves.  And the further down in that direction you go, the less energy each photon of the light has got.  So, the light which is actually dangerous itself is up in the ultraviolet which can give you cancer.

So, microwaves are probably not dangerous – they're certainly not dangerous with regards damaging cells chemically and giving you cancer.  You can obviously get too hot from them and overheat because, the piece of chicken in a microwave obviously is getting damaged because that's way it gets more tasty.  So, if you had a microwave with a hole in the back and you stood near it, then it would certainly be dangerous.  But as long as the microwave is properly designed and you're not standing right up next to it and kind of leaning over it and hugging it, there shouldn’t be a problem.

    And it won't do anything to the chemical composition of the food that you're heating up?

    It’s heating the food up in broadly the same way as any other means of cooking, just making it hotter.  The one difference is that it might not heat it quite as evenly.  So you might get parts of the food which have essentially been overheated and if you overheat food then you can reduce the amount of vitamins in it slightly.  So it’s not going to make it dangerous, but it might make it slightly less good for you.

How do kinetic watches work?

How do kinetic watches work?

If you have ever taken a cup of coffee or something with some foam on the top and spun the cup, the coffee stays still, but the cup turns around.  This is based on the same principles. 

There are some weights inside the watch which are free to move and as you move your wrist around, the weights tend to stay still when your wrist is moving, and so they move around and spin around as you move around, and go through your daily life.  This relative movement between the weight and the watch is connected to a little generator via some gears and cogs, and that charges the battery.  And so, as long as you keep using it and moving around, it will charge the battery up and it should keep going.

Is test tube cloning accepted by our society?

Is test tube cloning accepted by our society?


Clinton abolished any scientific research regarding cloning and Bush followed suit. However, parts of Europe are still doing some tests in this area.
Members of the UN are gearing up to debate highly the banning of human cloning.
The guise is really to hide behind medical research (more organs available such as hearts, kidneys for those who need them) but this is a highly dangerous area to get into. 125 scientific and patient organizations from around the world have signed and presented a letter to the UN.
One country of the UN, Costa Rica is backed by nearly 60 countries, including the U.S., for comprehensive banning on cloning. This includes both reproductive cloning to make babies, and the creaton of human embryos for use in medical research. Don't sit back and relax because cloning does go on under secrecy, so who knows what governments are involved.
The other group of countries, led by Belgium, and backed by over 20 countries, wants a ban on reproductive cloning only. They argue for the right of stem cells grown from cloned embryos might lead to cures for countless diseases. Span has switched away from supporting a blanket ban because of its change from a conservative to a socialist gov't., after elections in March 2004. Britain funds and supports therapeutic cloning.
It may come to a point that each country could quite possibly decide if their country should agree or disagree to cloning.
ARGUMENTS USED AGAINST AND IN DEFENSE OF HUMAN CLONING:
AGAINST:
Cloning might lead to the creation of genetically engineered groups of people for specific purposes, such as warfare or slavery.
Cloning might lead to an attempt to improve the human race according to an arbitrary standard.
Cloning could result in the introduction of additional defects in the human gene pool.
Cloning is unsafe. There are too many unknown factors that could adversely affect the offspring.
A close might have a dimished sense of individuality.
A clone might have fewer rights than other people.
Doctors might use clones as sources of organs for organ transplants
Cloning is at odds with the traditional concept of family.
Cloning is against God's will.
Some aspects of human life should ge off limits to science.
IN DEFENSE OF:
Cloning would enable infertile couples to have children of their own.
Cloning would give couples who are at risk of producing a child with a genetic defect the chance to produce a healthy child.
Cloning could shed light on how genes work and lead to the discovery of new treatments for genetic diseases.
A ban on cloning may be unconstitutional. It would deprive people of the right to reporduce and restrict the freedom of scientists.
A clone would not really bea duplicate, because environmental factors would mold him or her into a unique individual.
A clone would have as much of a sense of individuality as do twins.
A clone would have the same rights as do all other people.
Cloning is comparable in safety to a number of other medical procedures.
Objections to cloning are similar to objections raised against previous scientific achievements, for example, heart transplants and test-tube babies, that later came to be widely accepted.
As you can see Naruto, this is a complex issue. While many lives could be saved through more heart, liver, kidney transplants by cloning, in the wrong hands, armies could be created, and think of this: What if Hitler or Hussein could be cloned! Humans should be careful what they wish for.

Is fireworks called chemical reaction?

Is fireworks called chemical reaction?

Yes, gunpowder reacts with oxygen.


The oxygen comes from oxidizers perchlorates, chlorates, nitrates, permanganates, chromates or oxides.

In propelling the rocket, potassium nitrate is used with black powder. Chlorates or perchlorates are used for the explosion as it reacts with carbon and sulfur rapidly. For the different colours of firework, various metal salts are used.

Science has done more harm than good?

Science has done more harm than good?

Science has caused some atrocities, however it is also solely responsible for the survival of the sheer majority of the population.

For example. A single ammonia producing process (for fertiliser) discovered by science is now responsible for feeding 40% of the worlds population. That is about 3 billion people sustained by a single scientific process. However modern weapons would not exist without science. Science has been mostly applied for good, however there are a large amount of evils as a result too.

Science is neutral, what matters is how humans have applied it.

Name any 5 precautionary measures inside the laboratory?

Name any 5 precautionary measures inside the laboratory?

1. Familiarize your self with the laboratory.
2. Use a safety gear when necessary - particularly eye protection.
3. Follow your teacher's directions.
4. Practice correct or proper procedure in handling liquids.
5. Use your common sense.

6. Never smell a liquid reagent directly .
7. Never pour back a reagent in main bottle .
8. Don't eat or drink in lab.

9. Use fuming hood while working with volatile liquids .

When was nylon invented and do the letters NY and LON stand for New York and London?

When was nylon invented and do the letters NY and LON stand for New York and London?


 Nylon was invented by Wallace Carothers in 1935. There was a great demand for it as it was used for parachutes and tires. It is still used today in toothbrushes, stockings, fishing products, etc. A "nylon commuter" is someone who commutes between New York and London.
A number of "Brand Names " were developed by the inventing company, DUPONT Chemicals, such as NYLON, BANLON, ORLON and RAYON. All were types of woven textiles. Jim Bunting. Toronto. Actually, Jim, rayon was invented around 1885 and it is not a synthetic fiber as were the ones invented by DuPont. Instead, the original rayon was a regenerated cellulose (made from cotton linters and wood pulp).
Yes it does stand for New York and London as it was created by scientists from the locations. No it doesn't--see notes above.
In the UK we have a programme on the telly, hosted by Stephen Fry, called QI (Quite Interesting) & it assured me when I saw it recently that Nylon is nothing to do with New York & London ! Correct! See notes above.
Final answer, Nylon was not named after New York and London.

Why Clouds are White

 Why Clouds are White



 Not all clouds are pure white, however, for those that are white, it is due to their altitude and the reflection of sunlight.
For example, a cirrus cloud has an altitude of approximately 8km above sea level. At such extreme altitudes all high-level clouds are made up only of ice crystals, as the water vapor from which they are initially formed has frozen.
The ice crystals reflect sunlight. When flying above clouds during the day, they are always bright white. When we get dark clouds, they are so thick that they soak up most of the sunlight or reflect it upwards, and so things aren't as bright below. Storm clouds are the thickest clouds, and look the darkest from down below, though they still look bright white if we see them from above.

Gray color of the clouds is caused by higher clouds casting their shadow on lower-based clouds, or that the clouds are so dense that their top parts absorb most of the sunlight, casting their own shadow along their base, making them dark on the bottom. 

How does snow form?

How does snow form?

High up in the atmosphere, the air temperature is very cold. The water vapour may fall as rain if the water does not freeze. However, if the air temperature is so cold that the water droplets freeze, tiny ice crystals form in the clouds. These ice crystals collide with each other in the clouds or grow delicate shapes. The ice crystals combine to form snowflakes. There may be hundreds of tiny ice crystals in a single snow flake. These snow flakes fall from the clouds to form snow on the ground.

If the air temperature is not too cold and the air is very moist, the snow flakes may grow into very large flake up to 1 or 2 centimetres across.

Every snow flake is different. However, each snow flake has 6 sides.

What is sleet?

What is sleet?

When the air temperature is very cold, water vapour in clouds may fall as sleet, hail, or snow. Water droplets in the clouds get cold, but may not freeze completely. Sleet forms when partially frozen water droplets, or rainwater, in the clouds falls and freezes completely when it hits the surface of the Earth.

Like freezing rain, sleet may be dangerous because it coats roads and sidewalks with ice. Cars may not be able to stop on the slippery roads and many collisions between cars may occur. Slippery sidewalks are very difficult to walk along.

What is freezing rain?

What is freezing rain?

When the air temperature is very cold, water vapour in clouds may fall as sleet, hail, or snow. Water droplets in the clouds get cold, but may not freeze. Under certain circumstances, the temperature of the water droplet may drop below the freezing temperature of water, but the water remains in the liquid state. This water is super-cooled. When super-cooled water falls to the surface of the Earth, the water freezes instantly on any surface it hits. This is called freezing rain.

Freezing rain may cause lots of damage. Trees and power lines may break under the weight of the heavy ice. Cities may have to go without electricity when major power lines are broken.

How do clouds form?

How do clouds form?

As warmer air pass over the ocean or large open lakes, the air picks up water vapour. As the air warms, it rises because warm air is less dense than cold air. As the warm air rises, the air cools and the water vapour in the air condenses to form clouds of water droplets.

Clouds that form at the surface of the Earth are known as fog.

What is potential energy?

What is potential energy?

Potential energy is stored energy. An apple sitting on the edge of a table has stored potential energy. The potential energy changes to kinetic energy when the apple falls to the ground. A compressed spring has potential energy. That potential energy is converted to kinetic energy when the compressed spring is released.

What is energy?

What is energy?

Energy is the capacity to do work. Our energy comes from food, which contains stored chemical energy. Our bodies take the stored chemical energy and converts it to mechanical energy, heat energy or other forms of energy.

Light, sound, heat, and electricity are forms of energy

How does the sun produce photons?

How does the sun produce photons?

The surface of the Sun is very hot of course. It’s so hot that hydrogen becomes ionised into plasma so that you have photons and electrons as separate bodies, rather than bound together into atoms. And as those different charges interact, they exchange energy at the surface of the Sun and in the process of saving energy, they can lose energy and that is radiated as the photons that we see. Now that's not actually the powerhouse that drives luminosity of the Sun. That is the fusion of hydrogen atoms into helium which occurs at the core of the Sun. In fact, only in the central 20% or so of the Sun and so, you have another process which is convection which is carrying that heat which is generated at the centre of the sun out of the surface to keep the surface hot so that it continues to shine.

Are there no photons being produced deep inside the Sun? Presumably there are, but they just can't get out.

Photons are being produced all throughout the Sun, but the Sun is made of a cloudy material because these protons and electrons can interact with that light. And that means the photons produced deep down can only actually travel a few centimetres before they're reabsorbed.

And of course Bryan Fulton who was on this program, he’s professor of Astrophysics at the University of York. I think the point he made was that the photons that get made in the Sun are actually a million years old plus by the time they emerge because they have spent their entire life being bombarded around and absorbed and reabsorbed, ad infinitum almost before they finally escape. So if the Sun went out tomorrow, went out as in all reaction stopped, we’d still have a million years of the light locked inside.

The light is travelling at the speed of light, but it’s only hopping a few centimetres at a time and we don't know what direction it’s going to come back out again. It may end up going back towards the centre of the Sun again and it takes a million years. It’s quite a random walk for that energy to get to the surface.

Are air cavities in the body a problem when diving deep?

Are air cavities in the body a problem when diving deep?

It is a very good film and it does seem very futuristic, but it is actually partly reality. These chemicals, these liquids do exist. They're called perfluorocarbons. They include fluorohexane for example, so a string of 6 to 8 carbon atoms with lots of flourines hanging off the side and they're very good at dissolving oxygen. So, one way of doing this would be to instil these fluids into the respiratory tract and you saturate them with the oxygen, and then you move the fluid in and out, in the same way that you would when you were breathing.

Why this is helpful is that when a person descends underwater, the pressure they feel from the surrounding water goes up and up, the deeper they go. So, you have to therefore put the gas into the lungs to keep the lungs inflated, under progressively higher and higher pressures. One consequence of this is that it drives other gases like nitrogen and things into the tissues at extremely high pressures which means that then when you decompress, those gases come out of solution in the tissues and form bubbles which can cause the bends, they can cause damage to the brain, and cause damage to bones and muscles and so on. So if you use a fluid in the lung, because fluids are incompressible then you wouldn’t have the same problem because the fluid would withstand the pressure being applied by the outside water much better.

The issue with these fluids though is that they're not very good at removing CO2. They're very good at putting oxygen in. They're not good at getting carbon dioxide out and to compensate for the fact that they don't move CO2 very well, you'd have to move a lot of the fluid a lot of the time, and that's one of the major hold ups with doing this. In terms of the liquid getting into other body cavities and body parts, this isn’t such a problem actually. The eustachian tubes that you mentioned, they run between the back of the throat and the ear, so they would just fill up with the fluid anyway. The other body cavities, well, they wouldn’t actually be exposed to the fluid directly because it will be in the respiratory tree. So, there wouldn’t be a problem there and if there were any leakages of the fluid into other places, you would just pass it, I would think. It certainly wouldn’t become part of the systemic circulation, so it should be okay.

If dark skin absorbs more heat, why aren't native African people white, and Inuit people black?

If dark skin absorbs more heat, why aren't native African people white, and Inuit people black?

Logically, it should be the case that if you have pale skin it’s going to reflect more light and more heat and would be suited to warmer, sunnier places. But what is actually happening is people with darker skin have more melanin, more pigment, in their skin and this prevents the short wavelengths of light, the UV, from penetrating deep into the skin. It also means the skin can produce vitamin D in suitable levels. So if you live in more northern climes where there is less sunlight, so for example in the UK, then it’s much better to have pale skin which allows more sunlight to get into your skin and more vitamin D to be produced. Vitamin D is great for strengthening bones. Iit prevents you from getting diseases like rickets which would be very selective against a population if you were living in northern Europe.

UV radiation damages folic acid which you need for the development of the nervous system. If you get folic acid depleted you get diseases like spinabifida, so in continents like Africa where there is a lot of UV in the sunlight, if you don’t protect yourself with lots of melanin you will depete your folic acid, leading to an excess of neural tube defects like spinabifida and this would manifest in a cost to reproductive fitness in the population. So as there is so much sunlight, Africans can afford to have dark skin and still make enough vitamin D and not lose their folate but once you get up to the parts of the latitudes we live in, where it’s miserable all the time, vitamin D becomes the real problem. You need to make enough vitamin D and so you have to have pale skin. There’s so little UV because we hardly ever see the Sun anyway that it doesn’t become a problem from the folic acid depletion, neural tube defect perspective.

Are any viruses good for us?

Are any viruses good for us?

This may be true, despite that fact that most people think of a virus as being something that makes them feel awful! A recent piece of research in Nature by Skip Virgin, suggested that being infected by one of the family of viruses known as Herpes viruses, such as herpes simplex, which causes cold sores, Epstein-Barr virus, which causes glandular fever. When they infected mice with the rodent equivalent of those infections, the mice developed a much better immune system than mice which had ever been infected. To prove this, they exposed the mice to the bacteria which causes plague and also listeria, and they found these mice to be 100% protected against these bacteria compared with animals which had never been infected with a Herpes virus. When they studies these mice they found molecules called interferon gamma at a much higher level, and this molecule is known to stimulate the immune system.
They think that because we've been living with herpes viruses for millions of years, the body has come to rely on infection to provide additional gene function which our body no longer has. This stimulated the immune system and we get some benefit. It's almost a symbiosis, we give the virus a home and it gives us a better immune system.

Why does lightning rumble?

Why does lightning rumble?

If a lighting strike is very close to you it sounds like a very sharp crack and then a bit of a rumble afterwards, the further away you get the longer the rumble can sound. So a lightning bolt will make a sharp short noise, but first of all the noise is produced along a line up to a couple of kilometers long (if you live in Arizona), so because sound travels at 330m/s it could take up to 6 seconds for the sound from the top to reach you so the sound will be spread out over several seconds. The sound is then further spread out as you move further away from the lightning because the sound can get to you directly or by bouncing off things. This means that the sound will take lots of different times to get to you and therefore be spread out over several seconds as a rumble

How does food become radioactive?

How does food become radioactive?

there are various ways that food can become radioactive. It becomes radioactive when plants absorb it through their roots as they grow or animals ingest it and then you eat the animals. You also get fallout. So, in the initial blast where they vented the steam, there would’ve been some dissolved caesium and iodine, and probably some particles of fuel - very small amounts - in those vents, and those would have then come down around about the Fukushima prefecture. That's why the Japanese government has banned the sale of various different vegetables and milk within a certain radius of the plant.