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#1 Re: Ganesh's Puzzles » Series and Progressions » Today 16:25:01

Hi,

.

SP#535. In an Arithmetic Progression, given

. Find 'a' and
.

#2 Re: Ganesh's Puzzles » Coordinate Geometry » Today 16:03:54

Hi,

CG#33. The center of a circle is at (-6, 4). If one end of a diameter of a circle is at the origin, find the other end.

#4 Re: Ganesh's Puzzles » Mensuration » Today 15:41:20

Hi,

M # 532. Radius and slant height of a cone are 20 centimeters and 29 centimeters respectively. Find its volume. Use

.

#5 Re: Dark Discussions at Cafe Infinity » crème de la crème » Today 00:50:57

520) Henry Albert Fleuss

Henry Albert Fleuss (13 June 1851 – 6 January 1932) was a pioneering diving engineer, and Master Diver for Siebe, Gorman & Co. of London.
Fleuss was born in Marlborough, Wiltshire in 1851.

In 1878 he was granted a patent which improved rebreathers. His apparatus consisted of a rubber mask connected to a breathing bag, with (estimated) 50-60% O2 supplied from a copper tank and CO2 scrubbed by rope yarn soaked in a solution of caustic potash, the system giving a duration of about three hours. Fleuss tested his device in 1879 by spending an hour submerged in a water tank, then one week later by diving to a depth of 5.5m in open water, upon which occasion he was slightly injured when his assistants abruptly pulled him to the surface.

Fleuss's apparatus was first used under operational conditions in November 1880 by Alexander Lambert, lead diver of the Severn Tunnelconstruction project. Trained by Fleuss, he was able to close a submerged sluice door in the tunnel which had defeated the best efforts of hard hat divers due to the danger of their air supply hoses becoming fouled on submerged debris, and the strong water currents in the workings.

The same apparatus was later used several times to rescue mine workers in flooded workings.

Some time before the First World War, the Fleuss-Davis independent breathing set for hardhat divers appeared. This device consisted of two 10-cubic-foot (280 L) tanks, one each for compressed air and oxygen. The gases were mixed in a manifold between the two tanks and the diver's mouthpiece. The manufacturer claimed success of this unit to depths of 66 feet.

Fleuss also invented the Fleuss vacuum pump, which was a double action Guericke type pump which delivers an almost constant suction. It uses a cylinder divided in halves: as one half of the cylinder is filled with air, the other half is evacuating air to the atmosphere by one stroke of the pump. The next stroke reverses this action, producing the constant flow.

(Standard diving dress (also known as hard-hat or copper hat equipment, or heavy gear) is a type of diving suit that was formerly used for all underwater work that required more than breath-hold duration, which included marine salvage, civil engineering, pearl shell diving and other commercial diving work, and similar naval diving applications. Standard diving dress has largely been superseded by lighter and more comfortable equipment.)

(A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantially unused oxygen content, and unused inert content when present, of each breath. Oxygen is added to replenish the amount metabolised by the user. This differs from an open-circuit breathing apparatus, where the exhaled gas is discharged directly into the environment.)

Fleuss_Apparatus1.gif

#6 Re: Ganesh's Puzzles » 10 second questions » Today 00:43:55

Hi,

.

#7421. Find the value of y.
41% of 800 - 150 = y - 57% of 910.

#7 Re: Ganesh's Puzzles » Oral puzzles » Today 00:30:40

Hi,

#4479. The ratio of the boys and girls in a class is 6 : 5. If 8 more boys join the class and two girls leave the class, the ratio becomes 11 : 7. What is the number of boys in the class now?

#8 Re: Ganesh's Puzzles » General Quiz » Today 00:16:07

Hi,

#7239. What is 'Water gas'?

#7240. What is 'Producer gas'?

#9 Re: Ganesh's Puzzles » Series and Progressions » Yesterday 16:17:37

Hi,

SP#534. In an Arithmetic Progression, a = 7,

, find d and
.

#10 Re: Ganesh's Puzzles » Coordinate Geometry » Yesterday 16:02:04

Hi,

.

CG#32. Find the centroid of the triangle whose vertices are (3, -5), (-7, 4), and (10, -2).

#11 Re: Ganesh's Puzzles » Trigonometry » Yesterday 15:52:59

Hi,

.

T#100. Find sin x if

.

#12 Re: Ganesh's Puzzles » Mensuration » Yesterday 15:43:36

Hi,

M # 531. The radius and height of a cylinder are in the ratio 5 : 7. If its volume is 4400 cubic centimeters, find the radius of the cylinder. Use

.

#13 Re: Dark Discussions at Cafe Infinity » Did you know? » Yesterday 14:23:42

#30. Did you know?

The semi-major axis of Pluto's orbit varies between about 39.3 and 39.6 au with a period of about 19,951 years, corresponding to an orbital period varying between 246 and 249 years. The semi-major axis and period are presently getting longer.

#14 Re: Help Me ! » Reviewing area of polygons » Yesterday 13:58:47

Hi,

Area of a Regular Heptagon = The area (A) of a regular heptagon of side length a is given by:

Given, the Area is 130 square inches, the side length can be found.

Similarly, see the links:

Polygon

Octogon

Hexagon

Pentagon.

#15 Re: This is Cool » Miscellany » Yesterday 00:59:19

344) Bonsai

Bonsai, (Japanese: “tray-planted”) living dwarf tree or trees or the art of training and growing them in containers.

Bonsai specimens are ordinary trees and shrubs (not hereditary dwarfs) that are dwarfed by a system of pruning roots and branches and training branches by tying with wire. The art originated in China, where, perhaps over 1,000 years ago, trees were cultivated in trays, wooden containers, and earthenware pots and trained in naturalistic shapes. Bonsai, however, has been pursued and developed primarily by the Japanese. The first Japanese record of dwarfed potted trees is in the Kasuga-gongen-genki (1309), a picture scroll by Takashina Takakane.

The direct inspiration for bonsai is found in nature. Trees that grow in rocky crevices of high mountains, or that overhang cliffs, remain dwarfed and gnarled throughout their existence. The Japanese prize in bonsai an aged appearance of the trunk and branches and a weathered character in the exposed upper roots. These aesthetic qualities are seen to embody the philosophical concept of the mutability of all things.

Bonsai may live for a century or more and may be handed down from one generation to another as valued family possessions. Aesthetics of scale call for short needles on conifers and relatively small leaves on deciduous trees. Small-flowered, small-fruited varieties of trees are favoured. Open space between branches and between masses of foliage are also important aesthetically. In diminutive forests the lower portions of the trunks should be bare.

Good bonsai specimens are usually hardy species that can be kept outdoors the year round wherever winters are mild. They can be brought into the house occasionally for appreciation and enjoyment. In Japan they are customarily displayed in an alcove or on small tables in a living room and later returned to their outdoor bonsai stands.

The selection of the appropriate container in which to cultivate a bonsai is an essential element of the art. Bonsai pots are usually earthenware, with or without a colourful exterior glaze. They may be round, oval, square, rectangular, octagonal, or lobed and have one or more drainage holes in the bottom. Containers are carefully chosen to harmonize in colour and proportion with the tree. If the container is rectangular or oval, the tree is planted not quite halfway between the midpoint and one side, according to the spread of the branches. In a square or round container the tree is placed slightly off centre, except for cascade types, which are planted toward the opposite side of the container from which they overhang. Bonsai are trained to have a front, or viewing side, oriented toward the observer when on exhibit.

Although categorizations vary considerably, miniature bonsai are known broadly as shohin. The smallest of these (keishi and math) range in size up to about 2 inches (5–7 cm) in height and, started from seeds or cuttings, may take three to five years to come to quality stage. They may live several decades. Small bonsai (mame), 2 to 6 inches (7 to 15 cm) in height, require 5 to 10 or more years to train. Medium bonsai generally range from roughly 7 to 15 inches (20 to 40 cm) in height but can be up to about 2 feet (60 cm) tall and can be produced in as little as three years. Large (dai) bonsai can be as tall as 47 inches (120 cm) and require two or more people to move them.

Naturally dwarfed trees collected in the wild frequently fail to adapt to cultivation as bonsai because of the severe shock brought about by the change of environment and substrate.

Bonsai must be repotted every one to five years, depending on the species and extent of root growth. Gradual root pruning during transplanting in subsequent years reduces the size of the soil ball so that the tree can ultimately go into the desired small and shallow container. Water is usually provided on a daily basis; liquid fertilizer is also used. Pruning and nipping of shoots is performed through the growing season.

A bonsai industry of considerable size exists as part of the nursery industry in sections of Japan. The technique is also pursued on a small industrial scale in California.

1-250x250.jpg

#16 Jokes » Pilot Jokes - 1 » Yesterday 00:48:44

ganesh
Replies: 0

Q: What's the difference between a fighter pilot and God?
A: God doesn't think He's a fighter pilot.
* * *
Q: What's the difference between a pilot and a pepperoni pizza?
A: A pepperoni pizza can feed a family of four.
* * *
Q: What do you call when you're sick of being in the airport? A: Terminal illness.
A: Terminal illness.
* * *
Q: What do you get when you cross an airplane with a magician?
A: A flying sorcerer.
* * *
Q: Wanna know how to make a small fortune running a charter airline?
A: Start out with a large one.
* * *
Q: What do you call a plane that's about to crash?
A: An "Error Plane".
* * *
Q: What kind of chocolate do they sell at the airport?
A: Plane Chocolate!
* * *
Q: Why don`t ducks tell jokes when they fly?
A: Because they would quack up!
* * *

#18 Re: Ganesh's Puzzles » Oral puzzles » Yesterday 00:20:22

Hi,

#4478. Beena and Meena started a boutique investing an amount of $35000 and $56000 respectively. If Beena's share in the profit earned by them is $45000, what is the total profit earned?

#19 Re: Ganesh's Puzzles » English language puzzles » Yesterday 00:09:40

Hi,

#3227. What does the verb (used with object) detract mean?

#3228. What does the noun detriment mean?

#20 Re: Ganesh's Puzzles » Series and Progressions » 2019-05-19 16:27:58

Hi,

SP#533. In an Arithmetic Progression, a = 5, d = 3,

find n and
.

#21 Re: Ganesh's Puzzles » Coordinate Geometry » 2019-05-19 16:08:48

Hi,

CG#31. Find the centroid of the triangle whose vertices are (1, 3), (2, 7), and (12, -16).

#23 Re: Ganesh's Puzzles » Mensuration » 2019-05-19 15:19:23

Hi,

M # 530. Volume of a solid cylinder is 62.37 cubic centimeters. Find the radius if height is 4.5 centimeters. Use

.

#24 Re: Dark Discussions at Cafe Infinity » Did you know? » 2019-05-19 13:02:16

#28. Did you know?

The Electrochemical Society is a learned society (professional association) based in the United States that supports scientific inquiry in the field of electrochemistry and solid-state science and technology.

In November 1901, Charles John Reed set out on a mission to create a new society in order to more quickly and efficiently exchange information and ideas among those interested in electrochemistry. With the help of friend and professor Joseph W. Richards, the two men started what is the modern day Electrochemical Society.

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