Nokia mobiles are the world's leading mobile phone manufacturer. Nokia is a world leader in mobility, driving the transformation and growth of the converging internet and communication industries. Nokia mobiles are very demandable mobiles in Pakistan. Nokia offers wide range of mobiles set with different variation and price with latest technology. Find updated information of Nokia mobiles price in Pakistan, detail specifications and accessories.

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If you are wondering what is a compound light microscope?, then we will like to tell you that it is a light microscope which uses more than one lens to magnify the image. Light microscopes are of various types; some simple ones, like the one you have in your laboratory, or the more complex ones which are used by biologists. Magnification and resolution are two important features of a microscope. We will know more about these, but before that let us know a bit about the history of microscopes.

Zacharias Jansen of Holland can be credited with inventing the first microscope. His microscope had two lenses, one that magnified the image and another which further magnified the image produced by the first. The lens close to the eye was a bi-convex lens and the one farther from the eye was a plano-convex lens. These two lenses were mounted on two tubes which were placed in such a way that sliding one of the tubes altered the focus of the microscope.

In 17th century, Anton von Leeuwenhoek and Robert Hooke researched more on this subject and they discovered that to increase the magnification power of the microscope, the focal length had to be reduced. Leeuwenhoek's microscope was a single glass lens, whereas Robert Hooke's was a compound microscope having two lenses. With time, high quality lenses were used in microscopes and both, magnification power and resolution improved. Magnification and resolution are the two factors that determine the quality of a microscope. Magnification is the degree to which a sample is magnified when placed under a microscope. The light microscope magnification is calculated as

Magnification = Objective lens × Eyepiece lens

Resolution is the ability to distinguish between two tiny objects or a measure to which we get a detailed image.

Light Microscope Parts and Functions

Eyepiece lens: This is the lens from where you look at the image. The power of these lenses is around 10x.

Tube: The tube connects the eyepiece to the objective lenses. We will know about objective lenses later on.

Illuminator: To observe the specimen carefully, natural light may not be sufficient, so a microscope has a small bulb and the light from this bulb is redirected on the specimen by the means of a mounted mirror.

Base: The base is used to stabilize the microscope and makes it easy to move the microscope from one place to another.

Objective lens: The objective lenses are attached to the end of the tube. Normally, three to four objective lenses can be found in a microscope. The magnifying power of these lenses is in the range of 4X to 100 X.

Diaphragm: A diaphragm is used to alter the intensity of light projected on the interface.

Adjustment Knobs: The adjustment knobs help in observing the specimen in a better way, that is, they enable the user to get a highly magnified image. There are two adjustment knobs in a microscope. A coarse adjustment knob and a fine adjustment knob. The coarse adjustment knob helps in bringing the specimen in the right plane of focus, whereas the fine adjusting knob helps in clarifying a partially focused image.

Electron Microscope

Light microscopes are the oldest microscopes that are still being used, but the advances in science and technology has fueled the human desire to know more about his/her environment. There are certain organisms that are so small that they cannot be seen under a light microscope. To observe these organisms, an electron microscope is used. An electron microscope has a better resolution and greater magnifying power as compared to a light microscope. There are some differences between a light microscope and an electron microscope, let us take a look at them.

Light Microscope vs Electron Microscope

S.no.	Light Microscope	Electron Microscope
1	Affordable ($150 to $800)	Expensive (More than $1 50,000)
2	Easy to operate and carry	Requires expertize to use
3	Easy sample preparation	Sample preparation takes time
4	Original color of sample is maintained	Images are produced in black & white
5	Samples used can be living or dead	Only dead samples are used
6	Magnification power is 2000X	Magnification power is over 500,000X

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Is GPS Dangerous?
Like any new technology, GPS has its drawbacks. You have probably had at least one experience with a driver who swerves all over the road, speeding up or slowing down without warning, and is a danger to everyone in the vicinity, all because his attention is locked on the GPS navigator attached to the windshield. For those who aren’t lucky enough to have these systems in our vehicles, it seems strange that people would even want to have something like a miniature computer screen constantly obstructing their view of the road. This is becoming more and more common, though, and with GPS receivers built into cell phones, some drivers don’t even have the luxury of a map attached to their windshield. Instead, they drive with one hand, continually looking down at the maps on their phones, almost as if they expect the phone to drive for them, too.

The Unfounded Fear of Progress
Those who express such sentiments as these about new technologies are often labeled reactionaries and curmudgeons, and rightly so. After all, the new technologies that have made our lives better have often started out life in the midst of fear and criticism. Many people resisted microwave ovens at first due to a fear of their radiation output. Similar concerns were voiced about cell phones, which have since become an indispensable feature of contemporary life. So perhaps using GPS for everything only seems dangerous now; when this relatively new phenomenon has had some time to become more integrated with daily life, we will scarcely give it a second thought, and will laugh at the notion that we once thought it could be dangerous.

How Technology Changes People
However exaggerated these fears of new technology, it is perhaps fair to ask about their other effects on our lives. Maybe new technologies are not always as dangerous as we make them out to be, but they do have an undeniable and indelible effect on who we are as individuals. Take the microwave as an example. Today, people who are young or single can almost entirely avoid having to learn how to cook for themselves. Almost everything is available in a microwavable version, and there are even "cookbooks" that claim to instruct people how to use the microwave to their culinary advantage. Social networking is another popular example of this phenomenon: with the ability to interact online, interacting in person has become almost obsolete, and as a result far fewer people know how to do it.

How GPS Could Change People
One could argue all day about whether these changes are good or bad, and in the end it might be futile to have the discussion, because there are both good and bad aspects to any major social change. That the changes exist, though, is certain, and it would be truly foolish to claim that people have not changed as a result of these new technologies. In the case of GPS technology, the question that needs to be asked is: how are people changing as a result? If you or anyone you know has a smart phone with an excellent navigation system, you probably already know the answer to this question. People are coming to rely on these portable navigation systems in more and more instances. Those who once knew their way around a particular city, for example, may be forgetting how to navigate without their GPS systems.

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Who knew that a mere tablet PC could endow you with a fluttering peek of what does it feel like to hold the entire world in your hands? Who had an idea that it'd shush those inutile evaluators who harbored suspicion about it being a perfect replacement for laptops? While Android is having its nose to grindstone, having set out more than 80 tablets to kill the miracle called the Apple iPad, the developers of iPad repose in snugness, for the next generation iPad, the Apple iPad 2, is already seen in the cards. On January 27, 2010, the Apple fever among tech-savvies took a flight, for the first generation iPad broke through and how! Needless to say, it became a madness, a trend, a course, and of course, a must-have for every Apple lover. People anxiously waited for it to hit the stores, so that only once they could hold the beautiful king of tablets in their palm. To kick the bewilderment up a notch, that's happening again. Yes, you'll soon have in hand the new iPad, release date (2011) of which is set sometime in spring. That is to say, it's just round the corner, if the juicy iPad 2 rumors are to be presumed true. But what to expect from the new iPad 2? Today, let's draw something out of the interesting back-fence talks about the miracle that is soon going to take people's breaths away.

What is the New iPad Release Date

Rumors, rumors. Speculations on the Apple iPad 2 release date suggest that since iPad is being subjected to a considerable rise in the competition within the tablet market, it could launch the new iPad 2 quite soon. Tablets such as Motorola Xoom and Samsung Galaxy Tab (refer to Galaxy Tab vs iPad) have started to develop a good fan base, and are already being christened as the 'iPad killers'. Hence, it is extremely important for Apple to treat its fans with the iPad 2 at the earliest.

Another reason for Apple devotees to fervently expect the company to pass the word regarding when is the new iPad coming out is that since the first generation iPad was released in January, 2010 and shipped during Spring, chances are, something of similar sort could happen this year too. Hey, it's almost spring, innit? Tech veterans speak of the new iPad as something which is earnestly awaited, and hence, the sooner Apple launches it, the better it is for the company. After all, distractions, my friends, aren't good, or are they?

New iPad 2: What to Expect

If the buzz that's zooming with regards to when is iPad 2 coming out and what's new in it is to be believed, then you have all the reasons to buy this beautiful tablet, for Apple developers have read minds of their users. There was a reason the iPad market witnessed turbulence. It was because of the absence of a camera in the first generation iPad. Well, to save itself from witnessing users switching loyalties, rumors rife that the iPad 2 might have two cameras (8 MP or 10.2 MP back camera, and a front camera for video conferencing). That is believed to not only kick the iPad experience up a notch, but will also get Apple maximum hold of video conferencing-freak customers.

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