Science talk weekly
Monitors have come a long way over the years. Today we have a wide range of sleek looking flat screens, in a variation of sizes. These typically are Liquid Crystal Display monitors, better known as LCD monitors. Before I talk about the specifics of LCD monitors, a brief history of the older monitors that we once used. They were the large, heavy, box-like looking monitors called Cathode Ray Tube (CRT) monitors. These had physical vacuum-sealed tubes inside the box, that were filled with special gases. When electricity was passes through the gas, it would create different light colours that could be mixed to form the images you would see on the screen. When looking to buy LCD monitors, once again, as with all PC components, you can find a massive variation in the costs, depending on what model you want to purchase. Size is usually one main factor affecting price, where the larger the screen equates to greater cost. The other two main factors that will affect cost are screen refresh rates, and screen resolution. In simple terms, think of refresh rates as how many times per second the screen can update the image you see. The higher the refresh rate, the more times per second that the image can be updated. As a result, you should see a clearer image if the image is updated more frequently. Have you ever noticed if you are watching something move really fast on the screen it can start to blur? This blurring should be reduced with higher refresh rates. In computer monitors, this can be particularly important if you are playing games that have rapid, twitchy movements, particularly first person shooter (FPS) games like Call of Duty, or racing games. The units used to describe refresh rates are Hertz, abbreviated to Hz. Screen resolution is related to how many pixels are in the monitor. A pixel is like a small square that you can put a colour in. Each of the pixels on the screen act like a mosaic, where together they can be used to make a larger image. If you compared two screens of the same area with different amounts of pixels, the screen with more pixels should effectively have a better resolution, and a sharper image. Even in televisions, pixel counts are advertised, even though you may not realise this! A 1080p television will have a width of 1920 pixels and a height of 1080 pixels. The p doesn’t stand for pixels however, it relates to another factor which I won’t explain, but if you are curious, you can read more about it here: http://www.pcmag.com/article2/0,2817,2413044,00.asp
0 Comments
When one decides to build or buy a PC, the aesthetics are a factor that people consider. PC cases aren’t just about looks, design considerations also take into account computer performance. As mentioned in previous component articles, heating and cooling challenges are ever present in PC design. Cases can come in various shapes and sizes to optimize cooling, as well as being made from various materials to also assist in cooling. Once again, price seems to dictate design, where the highest performance cases, in terms of cooling potential, and aesthetic looks will be at the top end of cost. Ventilation is important for a case. Air flow is typically generated through positioned fans that will draw cool air from the outside, have it flow over the main motherboard heat sources, and push out the warm air. Some cases are designed to accommodate fully contained liquid cooling systems. These consist of a water pump, pipes, and a heat exchanger that can take the heat away from the heat sources (ie. CPU, GPU etc) instead of using air. Water can conduct heat better than air, however, the challenge of separating water from electricity is the main concern for water cooled systems. Have a look at your current case. Is it purely for function, or does it include aesthetics? Can you see through clear panels and see blinking coloured lights? Or is it just plain? Are there many vents with fans attached, or just one? Even the size and weight is taken into account. Big heavy cases may be cumbersome to transport, but may include greater metal surfaces that help heat transfer away from the CPU. The power supply is the source of electricity for your computer. The external part of the power supply will usually have a kettle cord socket, an on/off switch, and the back of a fan, which will be part of the power supply’s cooling system. On the inside of a PC, the power supply will usually have a number of smaller plugs that can be connected to hardware components within the computer. These include, the motherboard, any physical disk drives such as the HDD or DVD, and even other hardware components like a high powered graphics card. Power supplies will convert the wall power to the appropriate voltage required to run the computer. The will also vary in maximum amounts of electricity they can supply to the computer and its components. Larger power supplies will usually cost more, but this is one circumstance where having the biggest and best will not really benefit you PC much at all.
The hard drive, also known as the hard disk drive, is the physical component that all of the information is stored on within your computer. It can be abbreviated to HDD, and you may have seen this before. Over time as technology has improved, the amount of information the HDD can hold, or its capacity, has increased. The capacity of a hard drive is one of the main features that identifies this piece of hardware. The unit of measurement that is used to indicate a hard drive capacity is bytes. When reaching a certain amount of bytes, prefixes are used to indicate larger amounts. For example, 1000 bytes = 1 kilobyte. 1000 kilobytes = 1 megabyte. These units, as with all units, have abbreviations that are commonly used (think centimeters is cm and grams is g). Bytes are denoted by a B, kilobytes are kB, megabytes are MB, gigabytes are GB, terabytes are TB and so forth. Off the top of my head, our first home PC (back in the late 80s) had a hard disk drive capacity of about 40 megabytes, which for its time was great! These days, just one high resolution photo with my digital camera is about 40MB. If you were to pop into a computer shop to buy a new HDD, you probably couldn’t get anything smaller than 500GB. If you look at the calculation, 1GB = 1000MB, so 500GB = 500 000MB, which means what I could store on one hard drive today would have needed 12 500 computers that I had as a child. The type of hard drive I have been referring to are comprised of a series of disks (that look like DVD’s, but aren’t) which are called platters. The stack of platters are where the information is stored, and the information is stored as a magnetic signal. The platters are on a spindle, so they can spin around, and a needle will move to the correct location to access whatever information you have asked the computer to access. It works similar to how a needle would shift to different parts of a record to play different songs. There are another type of HDD called a solid state drive (SSD). They do not use the same technology as a traditional drive, and being more modern in their design, have many benefits over the older design. For a start, they don’t have any moving parts, which removes a factor of error that can occur with mechanical parts. Data retrieval is also much faster compared to a traditional HDD, and this is the main reason why you would want to choose an SSD over a HDD. As always though, with greater speed and power in computer comes a greater money cost. To compare the cost of a HDD to a SSD, I have taken prices from today’s (8 Oct 15) MSY price list (http://cdn.msy.com.au/Parts/PARTS.pdf), the 500GB Seagate Barracuda HDD is $63 compared to the 480GB OCZ Arc 100 is $248. You could therefore say, SSDs are approximately 4 times the cost of HDDs. Depending on what you need your PC to do, deciding whether to spend the extra money is one of many financial considerations you need to take into account when buying your PC. As with all of the hardware previously mentioned, the HDD (or SSD) plugs directly into the motherboard, and will usually require plugging into the power source, which will be next week’s hardware item in the spotlight.
The Graphics Processing Unit (GPU) is the fourth component in a series about computer hardware I am going to be talking about. They are typically referred to as a graphics card, because they look a little bit like a card that plugs into your motherboard. Graphics cards have come through many iterations over the past years, and are quite complex pieces of hardware. They are very similar to how your computer works. Being equipped with the information of the previous weeks, you will be able to appreciate how a GPU works. The card itself is made up of a board that has intricate circuitry in it. On the board are the components that do all the graphical processing for a computer. It is like a mini-motherboard, in that on a GPU there will be a processing unit(CPU), memory chips (RAM), and a heatsink for the processor. It also will have some ports and connections that will be visible from the outside of the PC, which provide the connections that allow you to plug your PC into a monitor. Part of the card will have the connections that allow you to plug it into its specific spot on the motherboard. There are different types of GPUs, and motherboards can be setup to take the different types. Some GPUs are designed to be able to run in parallel. The units can be bridged, or joined together, to get even more processing power out of your computer. The GPU is a specialized type of computer that does all of the calculations, drawing and rendering of graphics on your PC. When the computer accesses a program, the CPU will get all of the information and make it work. When there are graphics linked with the program, it then sends information to the GPU telling it to do the drawings. When you are playing a video game, first the GPU will draw a wire outline of the three dimensional object, then it will fill in all of the shapes with colour, and then do its final rendering and textures to complete the image. It doesn’t sound like too much, and you might be thinking, well the CPU could probably do it. Consider this, the GPU will do all of that 60 times per second, which can be quite an intensive job to do, especially if it is doing very rich and detailed fast moving images that one may encounter when gaming.
RAM is an acronym that stands for Random Access Memory, which probably doesn’t mean much at the moment, but as you have guessed, I’m about to explain. I’ve always thought of RAM like this: RAM is like the size of the desk you are working on. It doesn’t matter how fast you can work (or for a PC, how fast your CPU is), if you are trying to do a big job, and have hardly any space to work, it’s going to take you a long time. During high school, I had a small desk, and heaps of text books that I would use, as well as my exercise books. They would all pile up and when I was needing to access information, I was constantly shuffling through books, finding the information I needed, and then pulling out my exercise book, putting it on top of my other books so I could write in it, and homework would just take a long time. When I got to VCE, I got rid of my desk and started using a large table that was big enough to seat six people. Here I was able to lay out all of my texts books, and when I was studying, I could very quickly access all of the information I needed. RAM is the working memory of your computer. Whenever you are running a program or an application, the information is retrieved from another source, like a CD, DVD or hard disk drive(which I’ll explain in another post), and it is brought to the RAM. The more RAM you have, the more information you can have at the ready for your CPU to access. Some programs will require a lot of RAM to run efficiently, and other programs won’t need that much. Generally speaking, if I wanted better performance out of my PC I would first look at upgrading the RAM. Having more RAM (or more desk space) will allow the PC to have more information ready for use (more text books open), and hence should run quicker. There does come a point where you could have too much RAM, which won’t hinder your PC’s performance, but more so it’s just that you could have spent money elsewhere. If I go back to the desk analogy, if I had a stud of unlimited size, and say a 20m banquet table in it, and never wanted or needed to have more than 5 books open at one time, there’s no point to having such a massive table. I hope that sheds a bit more light on what RAM is, and how it fits into the overall picture of what’s happening inside your PC. This is what your typical stick of RAM looks like(above). The come in varying capacities, and simply plug into the motherboard. There are different variations outside of their capacity, so if you are upgrading, make sure your choice is compatible with your system. This is what a typical slot RAM on your motherboard looks like(above). You need at least one stick of RAM, but can use up to four. I have always had it recommended to me to go for a two stick kit that runs in the matching pair slots (ie both in yellow or both in orange). You can also see that in the bottom left of the picture is the white square socket where the CPU sits. It’s good to have the RAM as close to the CPU as possible. The smaller the distance the information needs to travel, the quicker it can work through calculations.
As always, many calculations means lots of energy is required and therefore lots of heat is produced – the bane of PCs. Just like the CPU, RAM can also come fitted with a heatsink, to assist cooling, and performance (below) Last week we spoke about the motherboard which is the large component that everything plugs into. This week we are going to look at the Central Processing Unit, more commonly known as the CPU. The CPU is the “brain” of your computer, and is responsible for doing many of the calculations. Whenever you turn on a computer, and run a program, the CPU is the main component that is doing all of the calculations and computations. I will continue to talk about Windows based PCs and not Apple, mainly because I don’t have any experience with pulling apart Apple computers to learn their interiors. The main brands that you would associate with CPUs are Intel and AMD. They have competitively been producing CPUs for as long as I’ve been using PCs, and there has often been a long running debate as to which is better. AMD or Intel? The CPU for its size is quite heavy, and this is due to the dense metal layer that sits on top of the circuitry. This metal is known as a heat sink. Its job is to absorb all of the heat that is produced inside of the processor. A large amount of electricity is passing through the CPU as it does its calculations, and as a result, lots of heat is made. Metal is an excellent conductor of heat, and with draw the heat away from the core. A large heatsink will be placed on top of the CPU, and then a fan will usually sit on top of that. It is important to keep the CPU cool in order for it to function efficiently. In some high end machines, water cooling technology is used to keep the system cool.
A lot of modern technology these days will contain a CPU. They are the “brain” of any computer. Next week, we will look at Random Access Memory, better known as RAM. To continue on from last week, I am going from simple circuits to more complex circuits – computers. My aim is to discuss the various main components you would typically find in a desktop computer. They are daunting to look at when you first open up a case, but once you get the hang of it, they really aren’t too bad. I first became interested in the internal workings of personal computers (PCs) in order to get more out of the family PC we had back in 1996. I wanted more RAM(which I’ll discuss in a future newsletter) so I could play better games. That’s one of the earliest memories I have of first learning what the hardware components are, what they do, and how they fit together. A PC is a jigsaw that works when you have everything plugged in the right place with the right compatibility. The first component I am going to talk about is the motherboard. The motherboard is the large, flat, plastic board that everything is plugged into. It has many plastic sockets and slots of different sizes and shapes, and many very fine metal circuits printed on the plastic. The board itself can vary in size and shape, which has pros and cons for the system as a whole. Motherboard full view with no components Over the years, I have noticed that the layouts of motherboards have constantly changed, and there are reasons for this. The locations of the components are carefully chosen to optimize the performance of the computer. When electricity moves through the circuits, it doesn’t go from place to place instantly, it takes time. When millions of calculations are being made, saving thousandths of a second by having the different components in the best spot affects the ultimate performance of the computer. Minimizing distances for faster computing isn’t the only consideration. Motherboards are also designed to help PCs stay cool, by allowing air to flow past the parts that get hot. Motherboard close up
If you are to open up a case, you typically will find the motherboard screwed into the inside of a PC case. The first blue picture is a motherboard for a standard desktop PC. I haven’t ever looked inside a Mac, so I’m not exactly sure what’s in them, but they would be very similar. If you ever get to see a motherboard of a laptop, they are similar, but have other considerations, mainly, being slim line and tightly packed to fit in the small laptop casing. I’d recommend, with supervision, that you check out inside a computer over the coming weeks, but please read the following warning: Make sure you are with an adult! Maybe even the person who bought it. Don’t just go opening any computer without permission. Computers are electrical, and can be dangerous if not treated with respect. Keep metal/conductors objects away from the inside. Opening a computer may void your warranty with the store it was purchased from, so check with them first. Try minimize the touching of all of the components inside the computer. The oils and residue on your hands can deposit on the surfaces, and hinder the performance. If you can, get some antistatic gloves before handling the hardware. And most importantly, be curious and HAVE FUN! When you turn on torch, have you ever wondered what is actually happening? Electricity is flowing from a power source, through the switch, to the light and back to power source. We call this a complete electric circuit. The circuit allows for electrons to flow around it, from the start, through to the light, and back to the start. Similar to a race track with race cars going around it, you must have a complete circuit for the electricity – and the cars – to make it back to the start. When you break the circuit, the electrons can’t flow, and the globe will no longer light up. The switch is the break in the circuit that allows you to control the flow of electricity. This is a simple circuit diagram that represents an electrical circuit. We always want to draw the diagram with the switch open (or off) so we can see easily where it is. In this diagram, no light would be coming from the light bulb. The flow of electricity starts from the batteries, goes to the switch, then the light bulb, and then back to the batteries. For more explanation on electric circuits, check out this clip: A lot of energy goes into getting people from A to B. When we fly aircraft, we need to use a lot of energy to oppose gravity, and get it off the ground. In an aircraft, lift is used to oppose the force of gravity. It is formed by having air pass over its wings. Thrust from the engines pushes the aircraft forward, and as a result, the air flows over the wings. In a modern day commercial aeroplane, jet engines provide the thrust required to allow flight at nearly the speed of sound. The way it works is to compress air, add fuel into the mixture, and then ignite the product. It really is an interesting process, it must have taken some ingenuity to develop. Here’s a good explanation of what’s going on inside a jet engine. Don’t you hate that feeling when your iPhone or iPad is on 1% and about to run out? Quickly darting to the charger to get it on before the device switches off entirely… We rely on electricity for so many things, though we probably don’t give too much thought about where the energy comes from. There is a need for us to be generating cleaner energy, and recent news has shown President Obama to be leading the way. A promise of reduced CO2 emissions, which will boost the need for renewable energy sources to be relied upon. Hopefully the Australian government will follow suit and push towards more renewables here too. Not only is it good for the environment, but it will rely on science to further develop its efficiency and understanding of renewable energy sources. This will create jobs, and hopefully boost interest in people selecting science as a career path to study and work in their future. From bbc.com/news
For more information on this news report, check out: http://www.bbc.com/news/science-environment-33731391 Are you starting your day with enough energy? What do you have for breakfast? I love to have toast in the morning, and the Aussie classic of Vegemite on toast is a common breakfast I, and many Australians will eat. But, is there something with more energy we could be eating to have an even better start to the day?
There are a number of different things we could put on our toast to fuel up for a busy day of school or work. Here are a number of sweet and savory ideas to help you start your day with enough energy! Ingredients you can use include: cream cheese, strawberries, pears, cheese, salmon, avocado, hummus, dates, herbs, chia seeds, egg, salami, beans, apple, prosciutto, cucumber, pomegranate, alfalfa, kiwi fruit, blackberries, blueberries, raspberries, raisins, sultanas, tuna, mango, and asparagus. Just like how a car needs fuel, your body needs fuel to function really well. Remember to always eat a balanced diet, as it is your source of energy. Also, don’t forget to drink plenty of water, it contains no energy that we can access, but will assist in digestion and keep your body functioning healthily. This term we will be focusing on Energy as our topic of discussion, and this also links to our theme for the up and coming Science Night which is about five weeks away. To start out though, I want you to think about renewable energy – what is it, what types are there, is there a future for renewable energy, and is it really even important? To understand where we are coming from, Australia currently gets the majority of its energy from non-renewable sources of energy, that is, coal. Coal is a fossil fuel that takes many thousands of years to create, though only has a few hundred years left before we have none left. The way it generally works is that we take coal as our fuel source, and burn it to boil water. Once we have boiled water, it turns to steam, and the steam is used to spin turbines. The spinning turbines then generate electricity which we then channel through copper wires to our homes, workplaces etc. Most of our coal plants are running off technology developed many years ago, and the process isn’t very efficient. About 70% of the energy released when burning coal is lost through the process, and then there is the issue of the by-products – that is, the pollution – that is created through burning coal. Carbon dioxide, also known as CO2, is a gas that interacts with other gases in the Earth’s atmosphere (mainly ozone) that are responsible for filtering out harmful ultraviolet (UV) rays from the sun. By burning coal, we create excessive amounts of CO2, which then breaks down the ozone layer that protects the Earth. We need to research and explore the avenue of renewable fuels as a country, because we can do it better, and have a responsibility to protect the Earth’s livelihood for the future. There are already countries that are using between 80 - 100% renewable energy sources, whereas Australia sits down at the 10-15% mark. According to some, this renewable source of wind energy is ugly and not worth pursuing. What do you think? How does it compare to coal (below)?
Solar power, as we know, is an important renewable energy source that is constantly being researched and improved. What are the limits of to where we can use solar power? During the long summer days where skies are clear, solar power is great as we can harness a lot of the sun's energy, but what if you live in a place that has low light or overcast weather? You just can't make enough energy for it to be a reasonable and viable option. Using solar technology to sustain powered seems impossible then, doesn't it? The Solar Impulse is the name of large solar powered aircraft that is currently attempting to navigate around the world. The project’s main aim is to demonstrate that alternate energy sources and new technologies can do what people think is impossible. Its purpose isn’t to revolutionise the aviation industry, but with all scientific ventures, there always is the possibility that this can pave the way for future research and adaptation, where solar technology may be incorporated into future aviation technology. It's such a high risk venture, yet human endeavor, the driving force of science, seems to be making this possible. The Solar Impulse team are maintaining an up to date website, documenting and displaying their journey. Check out www.solarimpulse.com to follow the progress of this modern day feat of science.
Lightning. It is a force of nature, and spectacular to look at, what is happening during a lightning strike? A natural force of nature, lightning is the build-up of static charge between clouds, and the ground. Scientists today still don’t fully understand what is happening in the process of lightning, but with better technology, they are learning more with time. Check out this video about lightning: When viewed in super slow motion, you can see how a lightning bolt is sending electricity in multiple directions, many times in the one flash: I hope you have heard of a galaxy, but if you haven’t, a galaxy is made up of many millions of stars, and the universe has many millions of galaxies! We are part of the Milky Way galaxy, but what is the brightest galaxy?
Scientists in California using the Wide-field Infrared Survey Explorer satellite, or the WISE satellite have discovered the brightest galaxy in the sky. The centre of the galaxy has a black hole, which is surrounded by a blazing hot disk of gas. This gas heats the surrounding dust, which then glows and sends infrared light (that’s the type of light that comes out of your remote control to change the television) back to the WISE satellite. Unlike the Milky Way, this galaxy doesn’t have a name like Snickers, Picnic or Mars, but it has the name W2246-0526. When a galaxy displays such hot temperatures, and is surrounded by dust, they are known as Hot Dust Obscured Galaxies, or, HotDOGs! For more information on this discovery, you can check out: https://www.sciencenews.org/article/brightest-galaxy-discovered or for the super enthusiastic, some information from the scientist who discovered it: http://wise5.ipac.caltech.edu/talks/Tsai.pdf As we have been talking about light this semester, this latest story comes from Tasmania. Along the Derwent River, blooms (or rapidly growing amounts) of a single celled organism called dinoflagellates have filled the waters. They are special and relate to light, because when they are physically moved, they light up, and emit a blue colour. When a living thing does this, it is referred to as bioluminescence, which means life (bio) lighting up (luminescence). It is unknown as to why this phenomenon occurs, yet with time, and usually money, scientists may figure out the reasons why it does.
If you want to know more, visit these website for more images, video and information. ABC Australian Geographic NASA took high resolution photos of the Sun for five years to create this short film. They used about 2600 terabytes of hard disk space to store these images. That's enough to fill 40,625 64Gb iPads.... How good are comics? Such a simple concept, three still drawings, but I’m sure we have all had this kind of moment that we can relate to, where nothing is worth doing, unless there is a tasty reward at he end. Where’s the science in this? Well, it’s in from transitioning from comics, to cartoons. The eye typically can see and recognise 12 – 15 still images per second. Once more images are shown per second, they brain will still being able to tell that they are still images, and they will start blurring into each other. Motion film for nearly 100 years now has used 24 images per second (or 24 Frames Per Second – 24FPS) . In recent times, with the advancement of technology, these FPS rates have increased, with films like The Hobbit being created at 48FPS, giving that realistic feeling to the experience. Everything seems so crisp and sharp. You can make your cartoons, with lots of time and patience. Check out this flip book to see how still images become moving images: The microscope is a fascinating piece of scientific technology. Similar to last week’s discussion on telescopes, microscopes originally used a series of lenses to magnify very small objects to a size that our eye can actually see. They are used in many different types of scientific research, and one can’t help but think of a scientist in a white lab coat looking down the barrel of an expensive microscope machine. Some of these microscopes can cost millions of dollars to make and service. Which left me thinking, how cheap could we make a microscope? A group of scientific researchers at the University of Houston have developed a microscope that can be attached to your smartphone, that allows you to zoom in 120 times! They have managed to develop this, where the end user cost would be a measly three cents! The lens that is the microscope is a small implement that would attach to the outside of your smartphone, over the camera lens. The lens is made from a viscous plastic polymer, with a similar consistence to honey, that is shaped in a way that is curved and allows light to be magnified. Top row shows human skin and hair follicle.
a) through c) are imaged with an Olympus IX-70 microscope at a magnification of 40, 100 and 200. d) is imaged with a Nokia Lumia 520 smartphone with a PDMS lens. Bottom row shows magnified regions. Credit: University of Houston For more information, you can go to Science Daily Basically, the Tesla Powerwall is a rechargeable battery, designed for use in your home. It is a Lithion-Ion battery, which isn’t a new technology in the context of rechargeable batteries, as these have been around for at least 10 years commercially – it’s the type that you would find in your smart phone. The beauty about this new product that has people amazed is the cost at which they have been able to develop and produce this new technology. There are other rival products that can do the same job as Tesla’s Powerwall, but are nowhere near as affordable. Check out some more information about the Powerwall. If you want one in your home, well, you will be waiting a while! They sold out very quickly, and the back order wait might take some time! Tesla Motors SMH News Report Treehugger Article All my life I have been fascinated with space, and spent countless hours as a kid staring at the stars with a bunch of constellation cards and a sky map trying to find more than just the Southern Cross and Orion. I think my interest was sparked by my brother, who for a school project took some long exposure photographs of different stars with a camera / telescope setup. It made sense, the telescope made a distant object seem closer, and the camera captured the image. But what was the telescope doing that my eye couldn’t?
A refraction telescope uses lenses to refract light into a size that can enter your eye, and make the object appear to be closer than what it actually is. Our eye has a lens that does this with light, the telescope is working in a similar way, except the lens can be a lot bigger than our eye. Being bigger allows it to collect more light, and therefore collect the light from objects that are further away. To find out more of the science behind the inner workings of a telescope, check out this BBC website. You can only make a refraction lens so big before they no longer can be effectively used within a telescope - cost, practicality and quality. Scientists have been able to develop larger, and much more expensive telescopes that use other technologies to reach further into space - checkout space.com for more information. |
How this beganWhat started out as a quick weekly Q&A in my school's paper newsletter has grown into an online multimedia science spot. Archives
October 2015
Categories |