Month: May 2014

Why didn’t Chris Lynn fall on the boundary rope while making the best catch in cricketing history?

In case you were wondering…
Also, would make for a very interesting exam question…

Answer by Mahek Mody:

Let's start with a slight detour – There is a very famous (& I think very cool) physics fact about pole vault. When a pole vaulter jumps a high bar, her Center of Gravity (CG) need not go as high as the bar she needs to clear. In other words, at the top of the jump the pole vaulter needs to go over the bar and not her CG. To achieve this the pole vaulter arches her back forwards or backwards to be in a situation where the body is clear of the bar but the CG passes under for the most optimal jump. The idea being that Newton's laws only dictate the trajectories of the CG and not the entire body.

Lynn's miraculous falling back within the boundary rope is something similar. After the little stumble he has just before he makes his jump, he has his eyes on the ball. Assess the trajectory of the ball, and it looks something like this –

Now Lynn considers jumping straight up and try get the ball. Is there a chance he can make it? His jumping ability is limited and there is only a limit to which he can raise his CG. He would not have caught the ball.

However, if he jumped and turned back at the same time things could look very different even if the his jumping ability is considered to be the same. As this diagram illustrates –

At this point if a snap was taken it seems as if he would fall on the boundary rope, but he has some angular (spin) momentum on his side which a still would not capture.

He does exactly that makes the catch and after which since his CG is still very much inside the boundary region he can easily use his flexible and agile body to bring his hands inside the boundary rope. Eventually using his hands to safely land well within the boundary.

I am sure Lynn did not go through all this physics in his mind before making the catch, but intuition is a powerful physics engine due to the world experience it has.

Cross posted on my blog – On the Boundary Lynn Catch

View Answer on Quora

The Kindle Paperwhite and Store: An Indian perspective

Amazon has been on a relentless journey since the Kindle launch in 2007, steadily making improvements to the product range to arrive at the perfect e-book reader. In the current era of pervasive LCD screens, the e-ink screens in the Kindle readers make for a paper like reading experience (albeit grayscale). This is the USP for dedicated e-book readers in the current tablet and smartphone era. The Kindle devices (apart from the large screen Kindle DX) have stuck to 6” screens that seem to be the ideal size, resembling your typical paperbacks. The devices started off with physical keyboards in the pre-iPhone era, and gradually evolved to a more compact form factor letting go of the keyboard in the Kindle Touch and 4th generation Kindle.

Hardware

The Kindle Paperwhite is the culmination of Amazon’s pursuit over the years, combining the essentials of an e-book reader with an attractive price point. Introduced in 2012 and upgraded last year, the Kindle Paperwhite is a near perfect e-book reader. The Pearl e-ink screen is of the de facto standard 6” size, with a 200+ dpi resolution resulting in print like readability and is the best of the current Kindle readers. There is also a special LED and fibre optics based backlight that can be adjusted to enable reading in poor lighting situations. In fact you can either turn off the light completely or turn it up to get rid of glare in most situations. While the first generation device had some complaints due to the non-uniform lighting in some devices, the second generation device has addressed this issue. Then there is also the touchscreen that makes for speedy navigation and organization of your collection. There are however no physical page turning buttons unlike the other Kindles, and this remains a bone of contention for some users. The touchscreen itself is not capacitive, but IR based due to which it can be activated by inadvertent contact with objects. It also supports multi touch (only 2 points though), and this can be used to adjust font size.

The device as a whole is quite lightweight (a little over 200 g which is around 50% heavier than a typical smartphone) and feels quite good in hand even though it is made of plastic with rounded edges. This also means that in case you doze off while reading on the bed, you are less likely to end up with injuries than your metallic tablets like the iPads. The Kindle Paperwhite has just one hardware button that functions as the power button. Apart from this the micro-USB port is the only discontinuity in the body. The device comes with just a USB cable in the box, and Amazon assumes that you have sufficient adapters at home to take care of the charging. Any standard USB adapter should do the trick for charging, and this is something that you will not need to do very often. Unlike smartphones with their daily and tablets with their near weekly charging requirements, the Kindle Paperwhite follows in its predecessor’s footsteps and gives a battery life of a month or more depending on usage. It’s been about 2 months since I bought my Kindle Paperwhite and have charged it twice thus far while having read over a dozen books.

The on device storage is just 2 GB with 1.25 GB usable for storing books. While that seems paltry by smartphone and tablet standards, e-books are typically text only and require very little storage space and the device should be able to comfortably accommodate hundreds of books, if not over a thousand. The Kindle Paperwhite also comes in 2 variants – Wi-Fi only and 3G, with a 20-30% premium for the latter. The 3G model is useful if you want to get hold of books on the go, but there are limits on the amount of data you can use per month since it comes with the connection built in (effectively Amazon subsidized) and you do not need to put in any SIM to use the network.

Getting content on the device is quite simple – just purchase your books from the Kindle bookstore. You can also side-load your own books into the device by connecting it to your PC, and add online articles and documents through mail.

Software

The Kindle Paperwhite user interface is pretty simple to use and there is a brief walkthrough of the features on your first power up. The home screen can be configured to display the covers of your book library or just a title list. The interaction is mostly gesture based with the screen split into 3 tap zones while reading – the top brings up the menu, the right 2/3 for page turning and left 1/3 for turning back. You can also swipe up-down\left-right to progress through lists. You can also organize your library into collections, which is particularly useful for large libraries. The top menu serves as a navigation system with a home and back button, a button to adjust the backlight, open up the Kindle Store and other menu items including font settings. There is also an experimental browser that you can use for web browsing in a pinch, along with social media integration to share snippets from the content you are reading.

The X-ray feature is also quite useful, particularly when you are reading books that have lots of characters and places. X-ray gives you snippets on the characters as they appear in the book along with visualization of areas where they feature. The second generation Paperwhite also has GoodReads integration for additional information on books, page flip that allows you to literally flip through the book without moving away from the page you are reading. You can also look up definitions of words and phrases in the built in dictionary and refer to Wikipedia as well. The touchscreen is quite handy for this purpose, and can also be used to highlight portions of the text.

The software on the whole is quite non-intrusive and fades into the background once you get reading and turning the pages which is precisely the reason for getting an e-book reader.

Amazon Kindle Store

The Kindle Paperwhite and other Kindle devices are but one side of the Amazon value proposition. The real reason why Amazon is producing the Kindle devices and selling them at a nominal profit is to rope you into their ecosystem which in this case is the Kindle bookstore. In fact, Amazon does not mind you using a different device like your smartphone or tablet as long as you are buying content from their bookstore. This is the reason they have got a Kindle App for every major platform including iOS, Android and Windows Phone. The devices and apps also sync your reading progress through the cloud, so you can continue reading from where you left off as long as you are signed in to your Amazon account.

Amazon has tuned the Kindle Store experience to minimize the amount of time you need to wait to start reading the book of your choice. Not only can you buy books directly from the Kindle Paperwhite when connected to a network, but you can also buy from the Amazon website and have it delivered to the device of your choice. In case you are unsure of the book content, you can also sample the first few pages for free. While this may not be a perfect substitute for flipping through a book in a physical store, the overall experience is a comprehensive improvement. Just the way Amazon revolutionized e-commerce, the Kindle Store lets you sample, buy and then start reading the book of your choice in the matter of a few minutes without stepping outside of what you were doing.

The Kindle US Store has been around for a while, but the Indian version launched only last year with e-books priced very aggressively – well below paperback editions. Many a times you will find bestsellers and popular books including new releases available at a fraction of paperback costs. The range is also extensive, and includes a good variety of Indian authors in addition to the typical international catalogue. There are also a range of photo heavy books available along with comics and graphic novels. These are however consumed best on large colour screen tablets due to their fixed layout. To round off the content availability, you can also subscribe to blogs, newspapers and magazines.

Conclusion

Amazon has completely transformed the way we purchase and read books over the years. It started off as one of the first successful online stores selling books, and then made e-books mainstream through the Kindle e-ink readers and the Kindle Store. Granted that a dedicated e-book reader may not be for everyone, especially when it is priced around Rs 10,000. This is the reason that Amazon also has the regular Kindle priced at a little over half of the Kindle Paperwhite for budget conscious readers. That device sacrifices the touchscreen and backlight along with some software features. In case you are looking for a general purpose device that also serves as a reader, Amazon has got you covered with the Kindle Fire devices that start just above the Kindle Paperwhite’s price.

That said, the Kindle Paperwhite in tandem with the massive collection in form of the Kindle Store makes for a very attractive value proposition. The device has an excellent backlit, sharp, paper-like screen with a multi-week battery life in a compact and lightweight form populated by the best bookstore in the world. If you have the budget, the Kindle Paperwhite is the best reading experience you can buy this year.

Note: An earlier version of this article appeared in On the Rox magazine