Toshiba Excite 10.1 Inch Tablets - Pure, Pro & Write Launched

Toshiba Corporation, the Japanese multinational company, has had an interesting line-up with its Excite series of Android tablets. Today adding new products to this series are three 10.1 inch tablets - the Excite Pure, Excite Pro and Excite Write. Along with these, Toshiba has also launched a keyboard dock which is optional and works with all the three new Excite tablets. With varied price tags, each of the three tablets has something different to offer that makes its stand out among its peers. For instance, Excite Pro and Excite Write models are the first Toshiba tablets to feature a 2560 x 1600 native screen resolution, currently the highest in the tablet market. Pushing an astounding 4 million pixels (300 pixels per inch), images, video and text come alive across the 10.1-inch PixelPure display2 with stunning color and razor-sharp clarity. These two also feature Harman Kardon stereo speakers, making them the first tablets to feature speakers from a premium audio brand. It's a increasing range of prices, with Excite Pure at $299, Excite Pro at $499 and Excite Write at $599. Let us take a look at each of these tablets one by one.

The Excite Pure tablet runs over Android 4.2.2 i.e. Jelly Bean OS and is trying to offer the complete Android experience, just without the external skins. The 10.1 inch screen has a resolution of 1280 x 800 pixels and is powered by the Nvidia Tegra 3 processor. The 3-megapixel rear-facing camera is all you have to capture photos and video. Offering
1GB DDR3 memory and 16 GB of internal storage, the presence of microSD card slot, assures the memory's expandability. You can connect the Excite Pure tab to TV or computer via the Micro-HDMI and Micro-USB ports.

Coming to Excite Pro, which bears a $499 maximum retail price, the tablet runs on a NVIDIA Tegra 4 mobile processor and features Android 4.2 Jelly Bean OS. Excite Pro comes with an 8-megapixel rear camera and 1.3-megapixel front one. There's 2 GB DDR3 and 32 GB internal storage and built-in Micro HDMI, Micro USB ports and a Micro SD slot. It is being said that there's high chance that Toshiba may be competing with the recently launched ASUS Transformer Pad Infinity tablet that offers similar specifications.

After checking the tech specs of the earlier two tablets, you will find that Excite Write'sfeatures are very similar to the Excite Pro. Besides the 10.1-inch PixelPure digitizer display (2560 x 1600) featuring Corning Gorilla Glass 2 and pressure sensitive Toshiba TruPen, there's NVIDIA Tegra 4 mobile processor, Android 4.2, Jelly Bean, 2GB DDR3, 32GB internal storage, an 8MP rear camera and lastly, built-in Micro HDMI, Micro USB ports and a Micro SD slot. This tablet comes with a Wacom digitizer that and makes it a direct competitor of the Samsung Galaxy Note 10.1 because of the pre-loaded apps called TruNote and TruCapture that assist with note-taking. This Wacom digitizer has support for 1,024 levels of pressure sensitivity.

All three tablet models will be available beginning on June 25, 2013 and can be purchased directly from Toshiba at ToshibaDirect.com or from major retailers and e-tailers nationwide beginning in early July. In an official press note, Carl Pinto, vice president of marketing, Toshiba America Information Systems, Inc., Digital Products Division said that, "With more and more consumers adopting tablets as their go-to devices for entertainment and travel, we wanted to push the boundaries even further and equip our new Excite tablets with the technology and features needed to maximize the potential of these devices." What are engineers here thinking of the price and features of the Excite series of tablets? Are they value for money? Share your thoughts with us in comments. 

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Sony Introduces Xperia M, A Sibling To The Flagship Xperia Z

The Xperia Z Has earned quite a lot of accolades for its new OmniBalance design, so taking this design to the mid/lower end market Sony has launched the Xperia M. On the front it has got a 4-inch FWVGA (854 x 480) display that is accompanied by a scratch resistant glass. The Xperia M runs Android 4.1 on a 1 GHz Qualcomm MSM8227 (dual core) processor with 1 GB of RAM. In terms of photography it has a 5 megapixel fast capture camera with auto-focus and HDR and a front VGA for video calls with a dedicated shutter key. The Xperia M also features colour-changing illuminations for notifications. In terms of internal memory it has a meagre 4GB out of which less than 2 GB is user accessible, however to make up this flaw Sony has included a microSD card slot expandable up to 64 GB.

The device features NFC, Bluetooth 4.0, Micro USB support, Native USB tethering and the regular Wi-Fi. A-GPS and Google maps take care of navigation and the phone will work dual band UMTS HSPA and quad band GSM networks. The smartphone will be powered by a user removable 1750 mAh battery that will give up to 10 hours of talk time and 498 hours of standby. The battery discharge cycle can be controlled by the ‘Stamina Mode’ of the phone with can be started by the user to prevent unnecessary applications from eating up your charge. Inside the box users can expect battery, charger and Micro USB cable. The phone will also have a dual SIM twin called the Xperia M dual which will run Android 4.2 (other specs are same as the single SIM model). The phones will be available in black, white and purple yellow colours globally in the third quarter of 2013 at an undisclosed price.

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Mahindra Verito Vibe Launch Tomorrow. Price Expected To Be Rs. 5.30 Lakh

Indian car maker Mahindra is all set to launch the new Verito Vibe tomorrow. The price of the car is expected to be about Rs. 5.3 Lakh ex-showroom in Delhi for the base varient. Looking at the teaser, it appears that Mahindra Verito Vibe is a compact saloon. It'll be a smaller (<4m) modification of the company's flagship sedan Verito. The company is expected to enter competition with the likes of Maruti Suzuki Swift, Ford Figo, Nissan Micra and others. The car is expected to be made available with Diesel engine at the launch and no Petrol varient has been planed. We'll only have to wait for official word on this tomorrow.

Because of the form factor and a smaller Renault K9K 1.5 liter dCi Diesel engine that outputs 68bhp, Vibe will enjoy excise duty benefits which will allow the car to be priced competitively. The car was first spotted during its trial run and suddenly gathered mixed reviews about its design.

AutocarIndia reports that the car was earlier expected to be a hatchback, but from the teasers, it seems to be a compact saloon with the boot hinged at the bottom of the rear windscreen. Mahindra has given the car a 2-box appearance instead of the 'chopped saloon' like that of Indigo eCS or Swift Dzire. 

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MTS Duet In India For INR 4,799 - A Dual SIM Budget-Friendly Smartphone

Mobile TeleSystems or MTS, the wireless voice, broadband Internet, messaging and data services company headquartered in Delhi, India is here with a new product of its own. The MTS Duet is a Dual SIM smartphone that supports CDMA as well as GSM networks. The company says that this is its 'strategy to offer greater choice' to users. Powered by a 1GHz Qualcomm Snapdragon processor, the MTS Duet features a 3.5-inch (8.8cm) display with capacitive touch screen that has a HVGA resolution of 320 x 480 pixels. As you can see the price cut has lead to a this low-end feature look of this smartphone.

The budget-friendly piece is running a top a Android 2.3 aka Gingerbread OS and gets booted up by driving power from a 1200mAh battery. There's an average 3 megapixel camera on the rear side and there’s no front lens. No word on the RAM or internal memory, but potential customers can expect a microSD card slot for expanding the hoarding space up to 32GB. The company’s Chief Marketing and Sales Officer for the country, Leonid Musatov, says that part from this CDMA- and GSM-happy dual SIM handset, there are plans to launch many more dual mode devices.

At a price in India of Rs. 4,799, the company is offering whatever good it can. There's a deal for unlimited data and local calls over 2 months to tempt the young audience who can't get their hands off SMS and prefer to be connected to their peers 24x7. So, interested buyers can choose to sign up for this bundle that costs Rs 599. Just two weeks back MTS had launched a dual-SIM budget phone which also works on CDMA and GSM technologies for its customers in Kolkata and West Bengal. The device is priced at Rs. 1699.

To make it easy for you to read the important, here are the tech specs at a glance -

• Android Gingerbread 2.3
• 1GHz Qualcomm Snapdragon S1 processor
• 3.5-inch display of 320 x 480p HVGA resolution and capacitive touch
• 3MP camera
• Dual SIM: CDMA and GSM networks
• 32GB expandable memory
• 1200mAh battery

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Lensless Camera Created By Bell Labs Never Goes Out Of Focus!

Image processing has undergone many innovations with time, which has always boosted up the quality. But it has always followed the same principle that it works on, that is, using a lens to create an image and a recorder to capture all the photons. Though the way these captured photons go through imaging has drastically changed with better and efficient algorithms, a new technique may bring in a revolution. The people at Bell Labs, New Jersey are calling it 'Compressive Sensing', which means that the data taken from the images are not much different from each other, but only have fractional changes in their measurements and are redundant. With compressive sensing they have built a camera with no lenses, using only a single sensing pixel, and the best part being that the image is never out of focus.

This technique could change optical, infrared and millimetre wave imaging. The camera is made up of only two components, an aperture assembly, and a sensor. The LCD panel allows the light to pass and a single sensor detects the three light colors of the image. Lesser the data in the scene, lesser data is recorded for imaging.

This device has many benefits over the conventional camera we have been using until now. There is less amount of data generated, no problems for bad focus since the whole image would be in focus and it would be cheap since the team has used cheap components to build the camera. The only thing bothering them is that the device takes a lot of time to collect the data and process the image of only still screens and the team is researching to overcome this. Another good thing about this would be that this principle can be used for the other wavelength of light too like infrared and millimetre waves, which could make it relatively cheaper.

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Saker S-1 - The Mach 0.99 Personal Jet With Operating Cost Of $2/Nautical Mile

If you are a busy businessman who doesn't want to wast time (and don't mind spending money to save time) then you might just look at the beautiful beast called Saker S-1. It's military jet inspired personal jet that aims to reach 0.99 aka almost equal to the speed of sound. The company says that it will cruise at a speed of Mach 0.95 and reach the top speed of Mach 0.99. This two seater plane will shave an hour off a 1500 nautical mile flight (approximately 2778 km) as compared to its closest competitor.

The Saker S-1 is designed to take off and land on runways as short as just 1500 ft. It can climb at the rate of 14,000 ft/min and have a service ceiling of about 45,000 ft. S-1has a maximum range of about 1600 miles (approximately 2575km) with its 1890 liter tank. The designers have added two external 380L tanks to increase the range to about 2200 miles (~3540 kilometers).

The craft has a wingspan of about 27ft and length of about 40.5 ft. It's 15 ft high and has empty weight of 2495 kg. The S-1 can carry maximum payload of about 2720 Kg. Two Williams FJ44-4 engines will power the aircraft and will serve for about 500 hours before needing an overhaul. The company says that the operational cost is about US $2 per nautical mile. It's also the aircraft that uses 20% lesser fuel than its competitors.

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World's Thinnest 500 GB & 1 TB HDDs Launched - Seagate & Western Digital

Looks like we've a war of the hard disks. Seagate recently announced the world's thinnest 500GB HDD that is just 5mm thick. The ultra-thin HDD looks like SSD and costs just $89. In the meanwhile, Western Digital too announced a 500GB HDD with very similar specs as that of Seagate. It's likely to find place in the new machines from ASUS and Dell. What's more interesting is that Western Digital has just announced another 'world's thinnest' 1TB hard drive that is just 2 mm thicker than its younger brother, at just 7mm.

The company claims that it features StableTrack which secures the motor shaft at both ends to reduce vibrations during operations and improve tracking. In addition there are dual-state actuators viz. electromagnetic for coarse displacement and piezo for the finer movements. SecurePark technology will keep the heads clear of the disk surface and also improve resistance to shocks. The company had demonstrated it at the IDF in 2012. The price of the 1TB model (WD10SPCXX) is $139 and that includes a 2 year warranty. Check the official press releases below -

WD® DELIVERS WORLD'S THINNEST 1 TB HARD DRIVE

New, 7 mm Slim 2.5-inch Hard Drive Delivers Industry's Highest Capacity Storage Giving Customers a High Capacity Option for Thin and Light Mobile Devices
IRVINE, Calif. – June 3, 2013 – WD®, a Western Digital (NASDAQ: WDC) company, today announced it is shipping the world's thinnest 1 TB hard drive with its new 2.5-inch WD Blue™ 7 mm hard drive. Offering OEMs, channel integrators and consumers a unique storage solution for thin and light systems, slimmer notebooks, as well as compatibility with the industry-standard 9.5 mm drive slots of mainstream notebooks, the WD Blue hard drive family, in capacities from 320 GB to 1 TB in the 7 mm height, now provides a singular option of thin design and high capacity storage.

"Users with large portfolios of content no longer need to sacrifice capacity when buying and Ultrabook or upgrading to a thin and light notebook," said Matt Rutledge, Vice President and General Manager for client storage products at WD. "This most compact 1TB hard drive to-date offers manufacturers of systems an upsell path for their customers who will now be able to choose systems offering both sleek design and high capacity.

"Intel is introducing its fourth-generation Intel Core processor family (codenamed Haswell) to deliver faster and more efficient performance to both desktop and notebook platforms, with significant gains benefitting portable systems" said Roger Bradford, Capabilities Marketing Manager at Intel. "The release of the WD Blue 7 mm hard drives offers a new level of storage capacity that further enriches the computing experience for users of Ultrabooks, All-in-Ones and other thin and light PCs."

"With the release of WD's 1 TB capacity in a 7 mm drive height, Acer customers now have the best of both options and no longer have to choose between the lightness of thin, sleekly designed systems or those with high capacity storage," said Tiffany Huang, BG President, PC Global Operations at Acer Incorporated.

"As ASUS develops new super-slim solutions, reliable storage options such as the WD Blue 7 mm 1 TB hard drive provide us with an ideal capacity to offer our customers," said S.Y. Shian, Corporate Vice President and General Manager of NB Business Unit at Asus. "WD has eliminated the capacity limits heretofore endured by thin and light personal computers while keeping the reliability and data-protection of a traditional hard drive."

Features of the WD Blue 7 mm hard drives include:

- Shock Tolerance – WD's ShockGuard™ technology protects the drive mechanics and platter surfaces from shocks.

- Cool and quiet - WD's exclusive WhisperDrive™ technology enables quiet performance.
- StableTrac™ – The motor shaft is secured at both ends to compensate for system-induced vibration and stabilize platters for accurate tracking during read and write operations which enables consistently higher performance.

- Dual Stage Actuators – Leveraged from enterprise-class drives, dual stage actuators utilize two actuators to improve positional accuracy over the data track(s). The primary actuator provides coarse displacement using conventional electromagnetic actuator principles. The secondary actuator uses piezoelectric motion to fine tune the head positioning to a higher degree of accuracy.

- Reliable – WD's SecurePark™ parks the recording heads off the disk surface during spin up, spin down, and when the drive is off. This ensures the recording head never touches the disk surface resulting in improved long term reliability due to less head wear, and improved non-operational shock tolerance.

- Compatibility Tested - WD performs tests on hundreds of systems and a multitude of platforms in its FIT Lab™ and Mobile Compatibility Lab to give customers confidence that drives will work in specific systems.

Price and Availability

Shipping now through select distributors and resellers, the new 1 TB WD Blue 7 mm 2.5-inch mobile hard drive is covered by a two-year limited warranty. MSRP for the 1 TB, model#: (WD10SPCXX) is $139.00 USD. Additional information about WD Blue mobile hard drives and limited warranty terms may be found on the company website at http://www.wd.com/en/products/products.aspx?id=800

INDUSTRY GIANTS LINE UP FOR SEAGATE ULTRA-THIN 5MM HARD DISK DRIVE

Laptop Ultrathin HDD Set to Redefine the Tablet and Mobile Computing Market

CUPERTINO, Calif. - June 3, 2013 -Seagate Technology plc (NASDAQ:STX), a world leader in storage solutions, today announced it's shipping its thinnest hard disk drive (HDD) ever to OEM partners - the Seagate® Laptop Ultrathin HDD. Just 5mm thin, the Laptop Ultrathin HDD is designed to be integrated into ultra-thin, lightweight mobile computing devices and tablets all while delivering high capacity storage at an affordable price.

"When we originally demonstrated this solution last September, we knew we had a truly innovative product that would empower our partners to reimagine mobile applications," said Steve Luczo, president, CEO and chairman of Seagate. "The strong support from our OEM partners indicates we have delivered on our vision and look forward to a new wave of innovative solutions enabled by this revolutionary product."

The 2.5- inch drive is just 5mm thin and weighs a mere 3.3oz- making it about as thin as four stacked credit cards and lighter than a deck of cards. It delivers up to 500GB of capacity in 25 percent less space than its previous-generation 7mm counterpart, freeing up valuable real-estate within portable devices to accommodate additional designed-in features such as longer-life batteries and better air circulation. An affordable alternative to SSD storage, Laptop Ultrathin HDD helps blur the lines between notebook and tablets by enabling new emerging applications like convertible and detachable storage.

"The new Seagate Laptop Ultrathin truly raises the bar, enabling us to finally create high-capacity, thin and light laptops that consumers crave at mass-market price points they can afford," said S.Y. Shian, corporate vice president and general manager of Asus' notebook business unit. "The drive's capacity, coupled with its ultra-slim, lightweight footprint, empowers our engineers to think out of the box and create truly ground-breaking, innovative system designs- it's a win- win for both us and the consumer."

Delivering the best cost per GB and cost per millimeter in the industry for ultrathin applications, the svelte high-capacity drive can support over 100,000 photos, 125,000 songs or 62 hours of high-definition video. The Laptop Ultrathin incorporates a 6GB/s SATA interface for fast data transfer rates and comes with the industry standard SATA connection for easy integration into existing laptops supported by both hard drive and SSD storage. SED encryption is available on the 500GB capacity version.

The Seagate Laptop Ultrathin has a manufacturer's suggested retail price of $89. For more information on the new Seagate Laptop Ultrathin HDD please visit http://seagate.com/www/ultrathin.

Strong Industry Support

"Dell's heritage is built on empowering our customers to do more with their technology investments with our unbeatable back-end expertise and cost-effective, tailored solutions that empower end-users and IT administrators alike," said Kirk Schell, vice president, personal computer product group, Dell. "Our partnership with Seagate on hard disk drive technology enables us to provide our customers with reliable, leading-edge, thin and light ultrabook and laptop designs with long battery life and uncompromised storage capacity."

"Portable devices have a voracious appetite for data, yet at the same time, owners demand thinner and lighter systems. Seagate has solved both by productizing the Laptop Ultrathin HDD," says Richard Doherty, research director for The Envisioneering Group. "Slimmer than a pencil, this revolutionary new hard disk drive gives freedom to designers and convenience to consumers and businesses alike."

"Our primary focus is to create IT solutions that deliver value. With consumers ever-increasing demand for high-capacity mobile computing devices, coupled with today's data-intensive applications, cutting-edge technologies such as Seagate's 5mm HDD are crucial for meeting end-user's expectations," said Wentao Yang, vice president of Lenovo global procurement. "And this new drive delivers on all fronts- not only enabling higher performance in many applications but also delivering high-capacity storage and providing consumers with a premium computing experience."

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Geyser - Cyclic hot water fountain

 

Geyser

 

Cyclic hot water fountain

 

Natural geysers form when underground chambers fill with water and are heated geothermally. When the water is heated to its boiling point, the geyser erupts, spewing its contents, and the cycle starts again. 

 

• Ring stand
• Metal ring
• Hot plate or other heat source
• Plastic food container
• Glass tubing (.5 to 1 meter in length)
• Boiling or Erlenmeyer Flask
• One-hole rubber stopper
• Plumber'sputty
• Timing device (stopwatch or clock)

1) Drill a hole in the center base of your plastic container (a sharp, pointed knife twirled in a circle makes a great drill). The hole should be just large enough for the glass tubing to be snugly inserted.

2) Position an unplugged hot plate next to the base of a ring stand and set a boiling flask filled with water on top of the heating unit.

3) Carefully insert one end of the glass tubing into the top of a one-hole rubber stopper. Slide the glass tubing until it is flush with the bottom of the stopper.

4) Cap the flask with the assembled stopper and glass tubing.

5) Slide a metal ring onto the ring stand and over the glass tubing (no need to tighten yet).

6) Insert the opposite end of the glass tubing into the base of the plastic container. Adjust the glass tubing so that the end extends several centimeters above the bottom of the container, but well below the container's rim. To prevent leakage, seal any gaps where the glass tubing and container meet with plumber's putty.

7) Place the center of the ring directly under the plastic container and tighten securely. This ring will be supporting the weight of the container and several cups of water.

8) Pour cool water into the plastic container. Fill the container with enough water so that the top of the glass tubing is a centimeter or two below the water's surface.

9) Turn on the heating element and stand back.

10) After the geyser "blows," it will reset itself by sucking the cool water from the plastic container back into the flask. Several eruptions will occur before the plastic container of water gets too hot and the temperature difference between the water in the flask and the water in the plastic container is not great enough to refill the system. When this happens, turn off or unplug the heating element and wait until the water in the plastic container cools.

• From a safe distance, watch what happens as the water heats and boils.
• How many different cycles can you discover in this geyser?
• Use your stopwatch to time and record the duration between eruptions and any other cycles you observe.

There are three main phases to this geyser's cycle: Heating, Erupting and Refilling.

Heating:
The heating time required to cause an eruption is based on two main factors: The energy output of the heat source and the length of glass tubing. The longer the glass tube, the more pressure there is on the flask of water. The more pressure there is, the more heat it takes for the water to boil and the longer it takes for the geyser to erupt.

Erupting:
Steam expands to over 1500 times its original volume and launches water out of the geyser (As the liquid begins to flow up the tube, it reduces the pressure in the chamber below. This in turn reduces the boiling point of the water causing a rapid conversion of liquid into steam).

Refilling:
After the eruption slows, a small amount of cool water in the upper container will flow down into the flask, causing the steam in the tube and flask to condense. This decreases the pressure inside the apparatus, allowing the atmosphere outside to push more water down into the flask.

Yellowstone National Park in northwestern Wyoming contains approximately 400 of the world's 700 geysers. Steamboat Geyser, located in Yellowstone's Norris Basin, is currently the world's tallest erupting geyser. Major eruptions can be over 350 feet tall.

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Gas Model - Caged molecules do their thing.

 

Gas Model

 

Caged molecules do their thing. 

 

The atomic theory of matter tells us that a gas is made up of tiny particles called atoms (or molecules, which are combinations of atoms), which are constantly in motion, smashing into each other and the walls of their container, if there is one. Here is a highly visual model of this idea. 

 

• 12 or more Styrofoam balls, approximately 1-1/4 inches (3 cm) in diameter (available in craft or fabric stores), or table tennis balls.
• A paintbrush.
• Latex paint.
• A small rodent cage with wire mesh on all sides. (Two plastic strawberry baskets or utility baskets with open grid sides may also be put together to form a cage.)
• Short pieces of wire or twist ties.
• A hair dryer, fan, or other blower.

15 minutes or less)

Paint one of the balls a bright color, using latex paint (because oil-based paint dissolves Styrofoam). Place the balls in the cage and secure the door of the cage with short pieces of wire or twist ties.

(15 minutes or more)

Hold the blower under the cage and blow air up through it. The moving air will agitate the balls, simulating the kinetic behavior of a gas. Watching the colored ball will allow you to follow the motion of a single "molecule."

By adjusting the speed of the blower from the cage, you can simulate heating and cooling a gas. The faster the balls are moving, the hotter the gas.

Listen for the clicking of the balls against the walls of the cage. At lower "temperatures," the clicking is quieter and occurs at a slower rate.

Adding heat (simulated by the blower) to a gas increases its internal energy. The molecules of the gas move faster and strike the walls of their container more often, yielding an increase in pressure (force per area). This increased pressure is simulated by the faster motion of the balls, which strike the sides of the cage more often. Cooling the gas (moving the blower farther from the cage) lowers the internal energy, slowing the motion of the molecules, and thus lowering the pressure.

You may want to try this Snack using cages of different volumes or try nesting baskets to change their volume. In this way, you can model the ideal gas law by changing temperature, pressure, and volume.

If you blow air on one side of the bottom of the cage and not the other, the balls will eventually "condense out." That is, they will form a pile on the side away from the blower, where it is "cooler."

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Fog Chamber - Make a portable cloud in a bottle. Now you see it; now you don't!

   

Fog Chamber

 

Make a portable cloud in a bottle. Now you see it; now you don't!

 

Clouds form when invisible water vapor in the air is cooled enough to form tiny droplets of liquid water. In the atmosphere, this usually happens when moist air cools as it rises to higher altitudes. At higher altitudes the pressure is lower, so that the gas expands, loses internal energy, and cools. You can accomplish the same cooling effect by rapidly expanding the air in a jar. 

 

• One 1 gallon (3.S liters) clear glass or plastic jar with a wide mouth (a pickle jar works well).
• A rubber glove (Playtex™ brand works well).
• Matches.
• Tap water.
• Adult help.

(5 minutes or less)

Barely cover the bottom of the jar with water. Hang the glove inside the jar with its fingers pointing down, and stretch the glove's open end over the mouth of the jar to seal it.

(15 minutes or more)

Insert your hand into the glove and pull it quickly outward without disturbing the jar's seal. Nothing will happen. Next, remove the glove, drop a lit match into the jar, and replace the glove. Pull outward on the glove once more. Fog forms inside the jar when you pull the glove outward and disappears when the glove snaps back. The fog will form for 5 to 10 minutes before the smoke particles settle and have to be replenished.

Water molecules are present in the air inside the jar, but they are in the form of an invisible gas, or vapor, flying around individually and not sticking to one another. When you pull the glove outward, you allow the air in the jar to expand. In expanding, the air must do work, which means that it loses some of its thermal energy, which in turn means that its molecules (including those of the water vapor), slow down slightly. This is a roundabout way of saying that the air becomes cooler!

When the water molecules slow down, they can stick to each other more easily, so they begin to bunch up in tiny droplets. The particles of smoke in the jar help this process along: The water molecules bunch together more easily when there is a solid particle to act as a nucleus. When you push the glove back in, you warm the air in the jar slightly, which causes the tiny droplets to evaporate and again become invisible.

In the atmosphere, air expands as it rises to regions of lower pressure and cools off, forming clouds. This is why clouds often obscure mountain tops. Dust, smoke, and salt particles in the air all provide nuclei that help the droplets condense.
Meteorologists consider a falling barometer reading (low air pressure) to be a sign of an approaching storm, whereas high pressure is usually a sign of clear weather. The temperature at which water vapor begins to form droplets on a surface is called the dew point.

For an added treat, shine a slide projector through the cloud you make in the jar. When the smoke is fresh, the droplets will be large compared to all wavelengths of visible light, and the light they scatter will be white. As the smoke dissipates, the water drops will become smaller, and the light scattered will create beautiful pastel colors at some viewing angles. Light of different colors diffracts around the small droplets, going off in different directions. If you look at clouds near the sun, you can often see bands of these pastel colors. (Remember, you should never look directly at the sun.)

For a longer discussion of this effect, see the book Clouds in a Glass of Beer  by C. Bohren (John Wiley & Sons, 1987).

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Far Out Corners - Your experience of the world influences what you see.

Far Out Corners

 

Your experience of the world influences what you see. 

 

When they first glance at this exhibit, many people say, "What's the big deal? It's just a bunch of boxes." But there are no boxes at all. A closer look reveals that the Far Out Corners exhibit is a cluster of corners lit from below. When you walk past the exhibit with one eye closed, the cubes will seem to turn mysteriously so that they follow your movement. 

 

• A large cardboard box measuring about 19 x 15 inches (48 x 38 cm).
• Flat black spray paint.
• Thick, white, nonflexible posterboard measuring at least 15 x 15 inches (38 x 38 cm).
• X-Acto™ knife or matte knife.
• Masking tape or transparent tape.
• A bright free-standing lamp.
• Adult help.

(1 hour or less) You can cut the inside corners from square-cornered containers, such as clean milk cartons or tissue boxes, or you can make your own corners from posterboard. To make your own, use an X-Acto™ knife or matte knife to cut the posterboard into nine squares, each of which measures 5 x 5 inches (13 x 13 cm).
Now use three of the squares to construct a partial cube or corner in the following fashion: Tape two squares together at one edge; open each of the two squares into a right angle; tape the third square on top of the first two squares. Make three partial cubes, or corners.



Spray-paint the inside of the large cardboard box black. When the box is dry, arrange the corners so that two are side by side on the bottom of the box, as shown. Make sure the hollow open sides of each corner are facing out toward you and down. Tape them so they are tilted up at a small angle. Place the third corner as far forward as possible on top of the original two, also tilted upward. Tape all three corners in place. Now position the light so that it shines directly into the box.

(15 minutes or more)Stand back ten feet and close one eye. With a little mental effort, you can see the corners that you have constructed as three-dimensional cubes rather than hollow corners.

Walk back and forth parallel to the box. Notice that the cube on top seems to be following you as you move.

The first step to successfully seeing the top partial cube turn with you lies in your ability to perceive it as a complete six-sided figure. This perception has a lot to do with being raised in a society that recognizes cubes as a common shape. Your brain is used to seeing cubes, so it fills in the rest of the cube shape, even though this partial cube only has three sides.

As you move past the exhibit, your view of the corners changes in a way that would not make any sense if the corners were stationary cubes. Your eye-brain system is used to seeing things that are near you move faster than things that are farther away. When you are riding in a car, for example, nearby objects seem to whiz by, whereas distant objects seem to follow you at a slower pace. Since you perceive this inside corner to be the outside of a solid cube, your brain "sees" the corner farthest from you as being the closest. To maintain this misconception, your brain perceives a rapid rotation of the cube as your angle to the corner changes.


The diagram above shows how this illusion works. In the real situation, as your eye moves to the right, it sees more of side A. In order to see more of side A of the imagined corner, the perceived cube must be seen to rotate as you move.
 

 

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