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#1 Re: Ganesh's Puzzles » 10 second questions » Yesterday 20:24:24

Hi,

The solution #6273 is correct. Neat work, zetafunc!

#6274. Find the value of

.

#2 Re: Dark Discussions at Cafe Infinity » crème de la crème » Yesterday 15:12:41

236) Manushi Chhillar

From CBSE topper to Miss World 2017, here's Manushi Chhillar's advice to youngsters

Little did we know that Miss World 2017 Manushi Chhillar was a CBSE topper in English.

"When you cease to dream you cease to live," quoted Miss World 2017 and added: "Courage to give flight to your dreams and the ability to believe in yourself  makes life worth living."  The 20-year-old Indian, Manushi Chhillar made the country proud by winning the prestigious title Miss World 2017 on Saturday.

Little did we know that Miss World 2017 was a CBSE topper in English. Chhillar did her schooling from St. Thomas School in New Delhi. According to a report in Tribune, "She was the CBSE topper in English and is associated with Shakti project on menstrual hygiene."

Moreover, she is pursuing Bachelor of Medicine, Bachelor of Surgery (MBBS) from Bhagat Phool Singh Government Medical College for Women in Sonepat.

Family background:

Her father, Dr. Mitra Basu Chhillar, is a scientist at the Defence Research and Development Organisation, while her mother, Dr. Neelam Chhillar, is an associate professor and the department head of neurochemistry at the Institute of Human Behaviour and Allied Sciences.

Advice to youngsters:

According to the official website of Miss World, Manushi Chhillar's advice to youngsters is: "Believe in yourself and never shy away from hard work. It does not matter what others think, 'beauty' is just perception. Get up every morning, tell yourself you are beautiful and gear up to win!"

(Miss World 2017, the 67th edition of the Miss World pageant, was held on 18 November 2017 at the Sanya City Arena in Sanya, China. 118 contestants from all over the world competed for the crown. Stephanie Del Valle of Puerto Rico crowned her successor Manushi Chhillar of India at the end of the event. This is the sixth time that India has won the Miss World, tying it for the most title wins with Venezuela.)

3_1028_1511063508_618x347.jpeg

#3 Re: Ganesh's Puzzles » 10 second questions » 2017-11-20 14:19:52

Hi,

The solution #6272 is correct. Neat work, Monox D. I-Fly!

#6273. Find the value of

.

#4 Re: This is Cool » Numbers ending in "9" » 2017-11-20 08:11:39

Hi kubes,

Nice post to start.

Welcome to the forum!

#5 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-11-20 00:39:27

235) Alexander Parkes

Alexander Parkes, (born Dec. 29, 1813, Birmingham, Warwickshire, Eng. - died June 29, 1890, West Dulwich, London), British chemist and inventor noted for his development of various industrial processes and materials.

Much of Parkes’s work was related to metallurgy. He was one of the first to propose introducing small amounts of phosphorus into metal alloys to enhance their strength. One of his most significant inventions was a method of extracting silver from lead ore. This procedure, commonly called the Parkes process (patented in 1850), involves adding zinc to lead and melting the two together. When stirred, the molten zinc reacts and forms compounds with any silver and gold present in the lead. These zinc compounds are lighter than the lead and, on cooling, form a crust that can be readily removed.

Another of Parkes’s important contributions was the discovery of the cold vulcanization process (1841), a method of waterproofing fabrics by means of a solution of rubber and carbon disulfide. Parkes also produced a flexible material called Parkesine (1856) from various mixtures of nitrocellulose, alcohols, camphor, and oils that predated the development of the first plastic, celluloid.

parkes_portrait.jpg

#6 Re: Ganesh's Puzzles » 10 second questions » 2017-11-19 22:43:19

Hi,

The solution #6271 is correct. Excellent, Monox D. I-Fly!

#6272. Find the value of

.

#7 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-19 22:36:22

Hi,

The solution #3836 is correct. Excellent, Monox D. I-Fly!

#3837. If the mode of the data : 64, 60, 48, x, 43, 48, 43, 34, and 43 is 43, find the value of x + 3.

#8 Re: Ganesh's Puzzles » 10 second questions » 2017-11-19 18:12:33

Hi,

#6271. Find the value of x if

.

#9 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-19 18:05:14

Hi,

#3836. Find the median of the first 10 prime numbers.

#10 Re: This is Cool » Miscellany » 2017-11-18 14:43:32

31) Bathyscaphe

Bathyscaphe, navigable diving vessel, developed by the Swiss educator and scientist Auguste Piccard (with assistance in later years from his son Jacques), designed to reach great depths in the ocean.

The first bathyscaphe, the FNRS 2, built in Belgium between 1946 and 1948, was damaged during 1948 trials in the Cape Verde Islands. Substantially rebuilt and greatly improved, the vessel was renamed FNRS 3 and carried out a series of descents under excellent conditions, including one of 4,000 metres (13,000 feet) into the Atlantic off Dakar, Senegal, on February 15, 1954. A second improved bathyscaphe, the Trieste, was launched on August 1, 1953, and dived to 3,150 metres (10,300 feet) in the same year. In 1958 the Trieste was acquired by the United States Navy, taken to California, and equipped with a new cabin designed to enable it to reach the seabed of the great oceanic trenches. Several successive descents were made into the Pacific by Jacques Piccard, and on January 23, 1960, Piccard, accompanied by Lieutenant Don Walsh of the U.S. Navy, dived to a record 10,916 metres (35,814 feet) in the Pacific’s Mariana Trench.

The bathyscaphe consists of two main components: a steel cabin, heavier than water and resistant to sea pressure, to accommodate the observers; and a light container called a float, filled with gasoline, which, being lighter than water, provides the necessary lifting power. The cabin and float are closely linked. On the surface, one or more ballast tanks filled with air provide enough lift to keep the bathyscaphe afloat. When the ballast tank valves are opened, air escapes and is replaced by water, making the whole device heavy enough to start its descent. The gasoline is in direct contact with the sea water and so is compressed at a rate almost exactly in proportion to the prevailing depth. Thus, the bathyscaphe gradually loses buoyancy as it descends, and the speed of its descent tends to increase rapidly. To slow down or to begin the reascent, the pilot releases ballast that consists essentially of iron shot stored in silos and held in place by electromagnets.

bathyscaphe_Trieste.jpg

#11 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-11-18 01:41:19

234) Harry Brearley

Harry Brearley (18 February 1871 – 14 July 1948) was an English metallurgist, usually credited with the invention of "rustless steel" (later to be called "stainless steel" in the anglophone world).

Life

Brearley was born on 18 February 1871 in Sheffield, England, the son of John Brearley, a steelworker, and his wife, Jane Brearley née Senior. He left Woodside school at the age of twelve to enter his first employment as a labourer in his father's steelworks, later getting the post of general assistant in the company's chemical laboratory. He married Helen Theresa Crank (1874–1955) on 23 October 1895. For several years, in addition to his laboratory work, he studied at home and later in formal evening classes, to specialize in steel production techniques and associated chemical analysis methods.

By his early thirties, Brearley had earned a reputation as an experienced professional and for being very astute in the resolution of practical, industrial, metallurgical problems. It was in 1908, when two of Sheffield's principal steelmaking companies innovatively agreed to jointly finance a common research laboratory (Brown Firth Laboratories) that Harry Brearley was asked to lead the project.

After leaving Brown Firth, Brearley joined Brown Bayley's Steel Works, also in Sheffield; he became a director of the firm in 1925.

In 1941 Brearley created a charitable trust The Freshgate Trust Foundation, a grantmaking charity operating in Sheffield and South Yorkshire. His aim was to provide a "Fresh Gate" or new opportunity to people like him born into modest circumstances so that they may experience the finer things in life such as travel, education, the arts and music. The foundation is still operating as a registered charity awarding grants for charitable purposes in South Yorkshire.

Brearley died on 14 July 1948, at Torquay, a coastal resort town in Devon, south west England. He was cremated at Efford Crematorium, Efford, near Plymouth on 16 July 1948 and his ashes were scattered in the Efford Crematorium Garden of Remembrance.

In 2013, in the Sheffield University Varsity Brewing Challenge, Sheffield University named their beer – brewed by Thornbridge – Brearleys, to commemorate 100 years since Harry Brearley invented stainless steel.

Stainless steel

In the troubled years immediately before World War I, arms manufacturing increased significantly in the UK, but practical problems were encountered due to erosion (excessive wear) of the internal surfaces of gun barrels. Brearley began to research new steels which could better resist the erosion caused by high temperatures (rather than corrosion, as is often mentioned in this regard). He began to examine the addition of chromium to steel, which was known to raise the material’s melting point, as compared to the standard carbon steels.

The research concentrated on quantifying the effects of varying the levels of carbon (C, at concentrations around 0.2 weight %) and chromium (Cr, in the range of 6 to 15 weight %).

The accidental discovery

In order to undertake metallography to study the microstructure of the experimental alloys (the main factor responsible for a steel's mechanical properties) it was necessary to polish and etch the metallic samples produced. For a carbon steel, a dilute solution of nitric acid in alcohol is sufficient to produce the required etching, but Brearley found that the new chromium steels were very resistant to chemical attack.

Development

It was probably Harry Brearley’s upbringing in Sheffield, a city famous for the manufacture of cutlery since the 16th century, which led him to appreciate the potential of these new steels for applications not only in high-temperature service, as originally envisioned, but also in the mass-production of food-related applications such as cutlery, saucepans and processing equipment etc. Up to that time carbon-steel knives were prone to unhygienic rusting if they were not frequently polished and only expensive sterling silver or EPNS cutlery was generally available to avoid such problems. With this in mind Brearley extended his examinations to include tests with food acids such as vinegar and lemon juice, with very promising results.

Brearley initially called the new alloy "rustless steel"; the more euphonic "stainless steel" was suggested by Ernest Stuart of R.F. Mosley's, a local cutlery manufacturer at Portland Works, and eventually prevailed although Mosley's used the "Rusnorstain" trademark for many years. It is reported that the first true stainless steel, a 0.24wt% C, 12.8wt% Cr ferrous alloy, was produced by Brearley in an electric furnace on 13 August 1913. He was subsequently awarded the Iron and Steel Institute's Bessemer Gold Medal in 1920. The American Society for Metals gives the date for Brearley's creation of casting number 1008 (12.8% chromium, 0.44% manganese, 0.2% silicon, 0.24% carbon and 85.32% iron) as 20 August 1913.

Virtually all research projects into the further development of stainless steels were interrupted by the 1914–18 War, but efforts were renewed in the 1920s. Brearley had left the Brown Firth Laboratories in 1915, following disagreements regarding patent rights, but the research continued under the direction of his successor, Dr. W. H. Hatfield. It is Hatfield who is credited with the development, in 1924, of a stainless steel which even today is probably the widest-used alloy of this type, the so-called "18/8", which in addition to chromium, includes nickel (Ni) in its composition (18wt% Cr, 8wt% Ni).

harrybrearly.jpg

#12 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-17 21:36:59

Hi,

The solution #3834 is correct. Excellent, Monox D. I-Fly!

#3835. If the median of the data : 6, 7, x - 2, x, 17, 20 written in ascending order, is 16. Find the value of x.

#13 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-17 18:56:09

Hi,

The solution #3833 is correct. Neat work, Monox D. I-Fly!

#3834. If the median of the data : 24, 25, 26, x + 2, x + 3, 30, 31, 34 is 27.5, then find the value of x.

#14 Re: Ganesh's Puzzles » 10 second questions » 2017-11-17 15:04:41

Hi,

#6271. If the angles A,B, and C of Δ ABC form an increasing Arithmetic Progression, then find the value of sin B.

#15 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-17 14:57:25

Hi,

#3833. If the Arithmetic Mean of x, x + 3, x + 6, x + 9, and x + 12 is 10, what is the value of x?

#16 Re: Introductions » Hi forum » 2017-11-15 14:29:10

Hi laurenwest144,

It's a pleasure!

#18 Re: Ganesh's Puzzles » 10 second questions » 2017-11-15 08:42:17

Hi,

#6270. The value of acute angle

is such that
, then find the value of
.

#19 Re: Ganesh's Puzzles » Oral puzzles » 2017-11-15 08:27:13

Hi,

#3832. If the mean of first n odd numbers is

, find the value of n.

#20 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-11-15 02:39:29

233) Jacques E. Brandenberger

Jacques Edwin Brandenberger (19 October 1872 – 13 July 1954) was a Swiss chemist and textile engineer who in 1908 invented cellophane. He was awarded the Franklin Institute's Elliott Cresson Medal in 1937.

Brandenberger was born in Zurich in 1872. He graduated from the University of Bern in 1895. In 1908 Brandenberger invented cellophane. Made from wood cellulose, cellophane was intended as a coating to make cloth more resistant to staining. After several years of further research and refinements he began production of cellophane in 1920 marketing it for industrial purposes. He sold the US rights to DuPont in 1923.

#21 Re: This is Cool » Miscellany » 2017-11-14 02:01:59

30) Angstrom (Angstrom unit)

The angstrom, also known as the angstrom unit, is a measure of displacement equal to 0.0000000001 meter

. It is sometimes used to express wavelength s of visible light, ultraviolet (UV) light, X rays, and gamma rays.


The visible-light spectrum extends from approximately 7700 angstroms (red light) to 3900 angstroms (violet light). This corresponds to frequencies of 390 to 770 terahertz (THz), where 1 THz = 10 12 Hz. Ultraviolet radiation, X rays, and gamma rays have progressively shorter wavelengths and higher frequencies. Some gamma rays have wavelengths less than
0.0001

angstrom.

The angstrom is not often used nowadays. It has been largely superseded by the nanometer (nm), which is 10 times larger; 1 nm = 10 angstroms =

m.

wavelength-color.PNG

#22 Re: Ganesh's Puzzles » 10 second questions » 2017-11-13 15:19:04

Hi,

The solution #6268 is correct! Keep it up, Monox D. I-Fly!

#6269. Find the value of 'x' if

#23 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-11-13 00:49:25

232) Satya Nadella

Satya Narayana Nadella (born 19 August 1967) is an Indian American business executive. He is the current Chief Executive Officer (CEO) of Microsoft, succeeding Steve Ballmer in 2014. Before becoming CEO, he was Executive Vice President of Microsoft's cloud and enterprise group, responsible for building and running the company's computing platforms, developer tools and cloud computing services.

Early life

Nadella was born in Hyderabad (now in the state of Telangana). His father, Bukkapuram Nadella Yugandher, was a civil servant of the Indian Administrative Service.

Nadella attended the Hyderabad Public School, Begumpet before attaining Bachelor of Engineering degree in electrical engineering from Manipal Institute of Technology (then part of Mangalore University) in 1988.

Nadella subsequently traveled to the U.S. to study for a Master of Science in Computer Science at the University of Wisconsin–Milwaukee, receiving his degree in 1990. Later he received his MBA degree from University of Chicago

Nadella said he "always wanted to build things" and that "electrical engineering was a great way for me to go discover what turned out to become a passion."

Career

Sun Microsystems

Nadella worked at Sun Microsystems as a member of its technology staff prior to joining Microsoft in 1992.

Microsoft

At Microsoft, Nadella has led major projects that included the company's move to cloud computing and the development of one of the largest cloud infrastructures in the world.

Nadella worked as the senior vice-president of Research and Development (R&D) for the Online Services Division and vice-president of the Microsoft Business Division. Later, he was made the president of Microsoft's $19 billion Server and Tools Business and led a transformation of the company's business and technology culture from client services to cloud infrastructure and services. He has been credited for helping bring Microsoft's database, Windows Server and developer tools to its Azure cloud. The revenue from Cloud Services grew to $20.3 billion in June 2013 from $16.6 billion when he took over in 2011. He received $18 million in 2016 pay.

Nadella's 2013 base salary was nearly $700,000, for a total compensation, with stock bonuses, of $7.6 million.

Previous positions held by Nadella include:

President of the Server & Tools Division (9 February 2011 – February 2014)
Senior Vice-President of Research and Development for the Online Services Division (March 2007 – February 2011)
Vice-President of the Business Division
Corporate Vice-President of Business Solutions and Search & Advertising Platform Group
Executive Vice-President of Cloud and Enterprise group

On 4 February 2014, Nadella was announced as the new CEO of Microsoft, the third chief executive in the company's history, following Bill Gates and Steve Ballmer.

In October 2014, Nadella courted controversy when he made a statement that women should not ask for a raise and should trust the system. The statement was made while he was attending an event on Women in Computing in Phoenix, AZ. Nadella was roundly criticised for the statement and he apologised later on Twitter. He later sent an email to Microsoft employees admitting he was "Completely wrong".

Nadella changed the company’s direction after becoming CEO. His tenure has emphasized openness to working with companies and technologies with which Microsoft also competes, including Apple Inc., Salesforce, IBM, and Dropbox. In contrast to previous Microsoft campaigns against the Linux operating system, Nadella proclaimed that "Microsoft ♥ Linux", and in 2016, Microsoft joined the Linux Foundation as a Platinum member.

Under Nadella, Microsoft revised its mission statement to "empower every person and organization on the planet to achieve more". In comparison to founder Bill Gates's "a PC on every desk and in every home, running Microsoft software", Nadella says that it is an enduring mission, rather than a temporal goal. His key goal has been transforming Microsoft’s corporate culture into one that values continual learning and growth. He has cited the book Mindset: The New Psychology of Success by Carol Dweck as inspiration for this philosophy around a "growth mindset".

Nadella's leadership of Microsoft included a series of high profile acquisitions of other companies, to redirect Microsoft's focus. His first major acquisition was of Mojang, a Swedish game company best known for the popular freeform computer building game Minecraft, in late 2014, for $2.5 billion. Minecraft was notably a cross-platform game, with versions running on Apple's iOS mobile devices, and the Sony PlayStation dedicated gaming console, as well as Microsoft's Xbox. He followed that in 2016 by purchasing Xamarin and LinkedIn.

In the years since becoming CEO, Nadella is viewed as having done well, with Microsoft stock having risen more than 60% since he took over, and achieving an all-time high.

Personal life

In 1992, Nadella married Anupama, daughter of his father's Indian Administrative Service (IAS) batchmate, K.R. Venugopal. The couple has three children, a son and two daughters, and live in Bellevue, Washington.

Nadella is an avid reader of American and Indian poetry. He also has an interest in cricket (his passion growing up), having played on his school team. He has mentioned having learned something about leadership and teamwork from cricket. He has a cricket bat signed by Sachin Tendulkar as his favorite personal possession.

In June 2016, it was announced Nadella would publish his first book, with a publish date planned for fall 2017. Titled 'Hit Refresh', the book will explore his life, Microsoft and how technology will shape the future. The profits from the book will be put towards Microsoft Philanthropies where it will go on to help nonprofits.

28517081_h32221057_wide-6382530f6cef158f1b54df809505976d2976112c-s800-c85.jpg

#24 Re: Ganesh's Puzzles » 10 second questions » 2017-11-12 19:51:57

Hi,

The solution #6267 is correct. Neat work, Monox D. I-Fly!

#6268. If

, find the value of x.

#25 Re: Ganesh's Puzzles » 10 second questions » 2017-11-12 14:40:11

Hi,

The solution #6266 is perfect. Excellent, Monox D. I-Fly!

#6267. If

, then find the value of
.

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