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A Ladder Is Formed By Rungs That Are Perpendicular To The Sides Of The Ladder. Explain Why The

A ladder is formed by rungs that are perpendicular to the sides of the ladder. Explain why the rungs of the ladder are parallel.?

The rungs are all perpendicular to the same sides of a ladder, so they are presumably oriented the same and are parallel to each other.
I will point out that rungs can be perpendicular to a shaft without being parallel. For example if the rungs formed a helical pattern like DNA, they would still be perpendicular to the long axis, but not parallel to each other.
For most ladders, the rungs will be parallel.

Each statement describes a ladder?

What can you conclude about the rungs, ones side, or both sides of each ladder?

examples:
1. The rungs are each perpendicular to one side.

2. the sides are parallel. The rungs are perpendicular to one side.

There's a whole bunch of these and I can't really comprehend what it's asking and it's hard to visualize a ladder that looks like what they explain. Because they all look extremely weird and unusable with the way I'm seeing them.

Explain a little, it you can?

How well did medieval armor work?

Very well. Gambeson, ( Padded linen armor ) was sturdier than you might think and unless a sword or axe or etc was very sharp it couldn't cut through it while maces and warhammers didn't do much at all because the padding absorbed the impact. Mail, was very effective at stopping cuts and most thrusts, tough not very good against blunt weapons but people often wore gambeson under mail armor so they were protected very well from both blunt and sharp attacks. Now we come to plate, the most protective and effective of them all. You could not penetrate plate, unlike what hollywood tells you. The only way of defeating someone in plate armor was to find gaps in the armor, and in the late medieval period, there were almost no gaps to be exploited. And even if there were gaps, they had mail covering the gaps. So plate armor was pretty effective. All kinds of armor were. And if you wonder about mobility in armor, gambeson and mail are pretty much like wearing clothing, only a little thicker with the gambeson and a little heavier with mail. If you wore a belt on your hips, the weight of the mail was evenly dispersed across your upper and lower body so it wasn't so hard on the shoulders. Plate usually weighed as much as the modern soldier's kit does. Although plate armor restricts your movements more than gambeson or mail, you are still very much capable of doing feats such as; Running, jumping, climbing ladders, getting on a horse and even do flips ! But being as heavy as it was, it did tire the user quicker. I didn't get into helmets or other parts of armor, or this post would be even longer. And I did talk mostly about the dominant types of armour in Scandinavia and Europe, so lamellar etc. not included. But as a summary, It works really well.

What are some specific, airtight examples to point to when arguing for government regulations/oversight, and against libertarians who think that the markets should shape our world?

Unfortunately you won't find any that work for two reasons.First it is safe to assume any example you provide showing poor outcomes from the private sector will be in an industry already loaded with government regulations. There is already an answer to this question using the financial crisis and love canal as examples. I am not seeing how using examples where massive regulation failed to solve a problem will support your case.Second if you manage to find one incident where an unregulated industry suffered bad outcomes and apply the same logic to government services you will find yourself supporting a logical framework with results you dislike. For example do the gross failures at the VA suggest the government should not be allowed to provide health care? Does the EPA dumping millions of gallons of toxins in the Colorado river mean the government shouldn't be allowed to manage the environment?I also wonder if regulation is really what you want.Here is an example of a typical government regulation from OSHA“The minimum perpendicular clearance between fixed ladder rungs, cleats, and steps, and any obstruction behind the ladder shall be 7 inches (18 cm), except in the case of an elevator pit ladder, for which a minimum perpendicular clearance of 4 1/2 inches (11 cm) is required.”Is this really what we want to spend resources on? Do you want people running around issuing fines for ladders that are 6.75 inches from the wall or would it perhaps be better to ensure the people behind the robo-signing mortgage scandal are punished? I firmly believe resources should be spent prosecuting corporate crime instead of pursuing nonsense like this.

Why is the Tower of Pisa tilted?

The leaning of the Tower of Pisa comes into the story in 1173, when construction began.Thanks to the soft ground, it had begun to lean by the time its builders got to the third story, in 1178. Shifting soil had destabilized the tower’s foundations.Over the next 800 years, it became clear the 55-metre tower wasn’t just learning but was actually falling at a rate of one to two millimeters per year.Today, the Leaning Tower of Pisa is more than five meters off perpendicular.Its architect and engineer tried to correct this by making the remaining stories shorter on the uphill side – but to no avail. It kept leaning more and more.The lean, first noted when three of the tower’s eight stories had been built, resulted from the foundation stones being laid on soft ground consisting of clay, fine sand and shells.The next stories were built slightly taller on the short side of the tower in an attempt to compensate for the lean. However, the weight of the extra floors caused the edifice to sink further and lean more.To know more about Pisa Top Attractions - Things to do in Pisa - Pisa Day trips .

Why are the frames of a heavy motor vehicle narrowed at the front?

There are basically several types of frames used for automobiles.The type of frame which is narrow at the front is known as Ladder Frame.So named for its resemblance to a ladder, the ladder frame is one of the simplest and oldest of all designs. It consists of two symmetrical beams, rails, or channels running the length of the vehicle, and several transverse cross-members connecting them. Originally seen on almost all vehicles, the ladder frame was gradually phased out on cars in favor of perimeter frames and unitized body construction. It is now seen mainly on trucks. This design offers good beam resistance because of its continuous rails from front to rear, but poor resistance to torsion or warping if simple, perpendicular cross-members are used. Also, the vehicle's overall height will be greater due to the floor pan sitting above the frame instead of inside it.

Is there a standard tread height for stairs? Is tread height governed by any particular building codes?

In the india we use following terms and general guidelines:(a) Tread: The horizontal top portion of a step where foot rests  is known as tread. The dimension ranges from 270 mm for residential buildings and factories to 300 mm for public buildings where large number of persons use the staircase. (b) Nosing: In some cases the tread is projected outward to increase the space. This projection is designated as nosing. (c) Riser: The vertical distance between two successive steps is termed as riser . The dimension of the riser ranges from 150 mm for public buildings to 190 mm for residential buildings and factories. (d) Waist: The thickness of the waist-slab on which steps are made is known as waist. The depth (thickness) of the waist is the minimum thickness perpendicular to the soffit of the staircase (cl. 33.3 of IS 456). The steps of the staircase resting on waist-slab can be made of bricks or concrete. (e) Going: Going is the horizontal projection between the first and the last riser of an inclined flight. The going should not be less than 250mm. General Guidelines: The respective dimensions of tread and riser for all the parallel steps should be the same in consecutive floor of a building. The minimum vertical headroom above any step should be 2 m. Generally, the number of risers in a flight should be restricted to twelve.  The minimum width of stair  should be 850 mm, though it is desirable to have the width between 1.1 to 1.6 m. In public building, cinema halls etc., large widths of the stair should be provided. Also angle of inclination is not more than 40 degree to horizontal.Also find below attached general thumb rule:

What is the structure of a DNA molecule?

A molecule of DNA is double-stranded. The molecule has the shape of a double helix, typically right handed (B form DNA).

The DNA molecule consists of two complementary strands oriented in an antiparallel fashion. Each strand is composed of nucleotides. A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.

The base of each nucleotide projects into the interior cavity of the helix. Each base is opposite another base: adenine (a purine) is always paired with thymine (a pyrimidine), and guanine (purine) with cytosine (pyrimidine); this phenomenon is called complementary base pairing.

Each nucleotide forms hydrogen bonds with its complementary base on the other strand. Two hydrogen bonds form between adenine and thymine; three hydrogen bonds form between guanine and cytosine.

There are three forms of DNA that differ significantly. The most common, B form, is the structure most people have heard of. It consists of the right handed double helix, with a large "major groove" and a smaller but accessible "minor groove". These 'grooves' are spaces between the backbone which allow access to the bases for interactions with proteins. A form DNA is also a right handed helix, but as yet has not been found in organisms, and only exists in synthetic environments. It has a wider, flatter structure. Z form DNA is found in living organisms, but is a left handed helix, meaning it twists in the opposite direction. Unlike A and B form DNA, the major and minor grooves have very similar sizes in Z form DNA.

The twisted ladder metaphor

A DNA molecule is often likened to a spiral (or twisted) ladder. In this analogy, the rungs of the ladder are the base pairs ( A-T and G-C). The sides of the ladder are the sugar-phosphate backbones of the two strands. This refers to B form DNA.

History of the double helix model

In an article published in the journal Nature on 25 April 1953, James D Watson and Francis H Crick proposed the double helix structure for DNA. Watson and Crick used unpublished information obtained empirically by Maurice Wilkins and Rosalind Franklin. In 1962 Crick, Watson, and Wilkins shared the Nobel Prize for Physiology or Medicine; Rosalind Franklin had died in 1958.mohimeen