Lever, simple machine consisting of a rigid bar that rotates about a fixed point, called a fulcrum. Levers affect the effort, or force, needed to do a certain amount of work, and are used to lift heavy objects. To move an object with a lever, force is applied to one end of the lever, and the object to be moved (referred to as the resistance or load) is usually located at the other end of the lever, with the fulcrum somewhere between the two. By varying the distances between the force and the fulcrum and between the load and the fulcrum, the amount of effort needed to move the load can be decreased, making the job easier.
Physicists classify the lever as one of the four simple machines used to do work. (The other three are the pulley, the wheel and axle, and the inclined plane.) Work is defined in physics as the result of a force, such as a person lifting, that moves an object over a distance. A common example of a lever is the seesaw. The human arm is also a lever, where the elbow is the fulcrum and the muscles apply the force.
Force? How force can produce effects on our position or position of any object which is in moving or rest condition. Force can disturb their position by applying it in proper direction and enough magnitude. Different types of force according to their application and point of application. A force system is also defined well with its different segments like - co planer, concurrent,co planer concurrent etc. Spring force, friction force, normal force, air resisting force, gravity force, tension force etc. described briefly.
Force? How force can produce effects on our position or position of any object which is in moving or rest condition. Force can disturb their position by applying it in proper direction and enough magnitude. Different types of force according to their application and point of application. A force system is also defined well with its different segments like - co planer, concurrent,co planer concurrent etc. Spring force, friction force, normal force, air resisting force, gravity force, tension force etc. described briefly.
Simple machines by Saliha Rais, for grade 5.Saliha Rais
The slide show include topics: simple machines, force magnifiers, movement magnifiers, levers and its types. At the end there is a short review/test, so you can assess what you have learned.
I made this for grade 5 students.
the relation between force and motion id described in Newtons three laws of motion. These laws are very simple statements and enable us to describe the future (or past) motion of body if we know the forces acting on it.
Force, types of forces and system of forcesKhanSaif2
This presentation covers concept of force and different types of forces as well as different system of forces. I hope this PPT will be helpful for instructors as well as students.
Simple machines by Saliha Rais, for grade 5.Saliha Rais
The slide show include topics: simple machines, force magnifiers, movement magnifiers, levers and its types. At the end there is a short review/test, so you can assess what you have learned.
I made this for grade 5 students.
the relation between force and motion id described in Newtons three laws of motion. These laws are very simple statements and enable us to describe the future (or past) motion of body if we know the forces acting on it.
Force, types of forces and system of forcesKhanSaif2
This presentation covers concept of force and different types of forces as well as different system of forces. I hope this PPT will be helpful for instructors as well as students.
Description of motion and forces .
Lever and there implication on the human body.
This will help you in understanding the Lever system in a better way.
One of the best known mathematical formulas is Pythagorean Theorem,Over 2000 years ago there was an amazing discovery about triangles:
When a triangle has a right angle (90°) and squares are made on each of the three sides,then the biggest square has the exact same area as the other two squares put together! Maths is Fun
"The Ransom of Red Chief" is a 1910 short story by O. Henry first published in The Saturday Evening Post. It follows two men who kidnap and attempt to ransom a wealthy Alabaman's son; eventually, the men are driven crazy by the boy's spoiled and hyperactive behavior, and end up having to pay the boy's father to take him back.
The story and its main idea have become a part of popular culture, with many children's television programs using a version of the story as one of their episodes. The tale is a light-hearted example of the ultimate in "poetic justice" and fortuitous intervention for the public good: the crooks had intended to use the ransom money to fund an even larger and much more elaborate scam that would likely have caused widespread monetary damage to the local populace, and so having their plans "foiled in their infancy" by Red Chief's shrewd father saves countless other honest folks from financial ruin. It has also been often used as a classic example of two ultimate comic ironies—a supposed "hostage" actually liking his abductors and enjoying being captured, and his captors getting their just deserts by having the tables turned on them, and being compelled to pay to be rid of him.
Symmetry (from Greek συμμετρία symmetria "agreement in dimensions, due proportion, arrangement")[1] in everyday language refers to a sense of harmonious and beautiful proportion and balance.[2][3][a] In mathematics, "symmetry" has a more precise definition, that an object is invariant to any of various transformations; including reflection, rotation or scaling. Although these two meanings of "symmetry" can sometimes be told apart, they are related, so they are here discussed together.
Mathematical symmetry may be observed with respect to the passage of time; as a spatial relationship; through geometric transformations; through other kinds of functional transformations; and as an aspect of abstract objects, theoretic models, language, music and even knowledge itself.[4][b]
This article describes symmetry from three perspectives: in mathematics, including geometry, the most familiar type of symmetry for many people; in science and nature; and in the arts, covering architecture, art and music.
The opposite of symmetry is asymmetry.
In geometry[edit]
Main article: Symmetry (geometry)
The triskelion has 3-fold rotational symmetry.
A geometric shape or object is symmetric if it can be divided into two or more identical pieces that are arranged in an organized fashion.[5] This means that an object is symmetric if there is a transformation that moves individual pieces of the object but doesn't change the overall shape. The type of symmetry is determined by the way the pieces are organized, or by the type of transformation:
An object has reflectional symmetry (line or mirror symmetry) if there is a line going through it which divides it into two pieces which are mirror images of each other.[6]
An object has rotational symmetry if the object can be rotated about a fixed point without changing the overall shape.[7]
An object has translational symmetry if it can be translated without changing its overall shape.[8]
An object has helical symmetry if it can be simultaneously translated and rotated in three-dimensional space along a line known as a screw axis.[9]
An object has scale symmetry if it does not change shape when it is expanded or contracted.[10] Fractals also exhibit a form of scale symmetry, where small portions of the fractal are similar in shape to large portions.[11]
The idea that nature can harm us is not new. Have you ever heard of malaria, HIV, tuberculosis, botulism or tetanus? Why, then, are so many convinced that anything and everything natural is healthier for us than synthetic products? It's true that modern chemistry has brought us a number of toxic chemicals, like DDT and dioxins, but do you really think that nature's chemicals are any less harmful to you? In fact, the most toxic chemicals to humans are completely natural! Not only that, but there is much evidence that natural pesticides allowed in organic farming are just as toxic as synthetic pesticides. It would be wonderful if it were simply a black versus white topic.
Unfortunately, the natural versus synthetic debate falls very much in the gray region, and each and every chemical, or class of chemicals, must be considered on a case by case basis. To make the situation more frustrating, the number of useful and accessible resources for consumers is limited, since the majority of the “information” on the internet and in the news is unfounded and unreferenced. It’s no wonder that this idea has been able to take hold so well! The purpose of this post is to briefly discuss the most common misunderstandings about natural and synthetic chemicals:
1. Synthetic chemicals are more toxic than natural chemicals.
2. Organically grown food is better for you because it’s all natural.
3. Synthetic copies of natural chemicals are not as good for you.
Fungus, plural fungi, any of about 99,000 known species of organisms of the kingdom Fungi, which includes the yeasts, rusts, smuts, mildews, molds, and mushrooms. There are also many funguslike organisms, including slime molds and oomycetes (water molds), that do not belong to kingdom Fungi but are often called fungi. Many of these funguslike organisms are included in the kingdom Chromista. Fungi are among the most widely distributed organisms on Earth and are of great environmental and medical importance. Many fungi are free-living in soil or water; others form parasitic or symbiotic relationships with plants or animals.
A fungus (/ˈfʌŋɡəs/; plural: fungi[3] or funguses[4]) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from the other eukaryotic life kingdoms of plants and animals.
A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Similar to animals, fungi are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesise. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the Eumycota (true fungi or Eumycetes), which share a common ancestor (form a monophyletic group), an interpretation that is also strongly supported by molecular phylogenetics. This fungal group is distinct from the structurally similar myxomycetes (slime molds) and oomycetes (water molds). The discipline of biology devoted to the study of fungi is known as mycology (from the Greek μύκης, mukēs, meaning "fungus"). In the past, mycology was regarded as a branch of botany, although it is now known fungi are genetically more closely related to animals than to plants.
Abu'l-Fath Jalal-ud-din Muhammad (15 October 1542[a]– 27 October 1605[10][11]), popularly known as Akbar I (IPA: [əkbər], literally "the great") and later Akbar the Great,[12] was the third Mughal emperor, who reigned from 1556 to 1605. Akbar succeeded his father, Humayun, under a regent, Bairam Khan, who helped the young emperor expand and consolidate Mughal domains in India. A strong personality and a successful general, Akbar gradually enlarged the Mughal Empire to include nearly all of the Indian Subcontinent north of the Godavari river. His power and influence, however, extended over the entire country because of Mughal military, political, cultural, and economic dominance.
e-commerce is a transaction of buying or selling online. Electronic commerce draws on technologies such as mobile commerce, electronic funds transfer, supply chain management, Internet marketing, online transaction processing, electronic data interchange (EDI), inventory management systems, and automated data collection systems. Modern electronic commerce typically uses the World Wide Web for at least one part of the transaction's life cycle although it may also use other technologies such as e-mail.
e-commerce businesses may employ some or all of the following:
Online shopping web sites for retail sales direct to consumers
Providing or participating in online marketplaces, which process third-party business-to-consumer or consumer-to-consumer sales
Business-to-business buying and selling
Gathering and using demographic data through web contacts and social media
Business-to-business (B2B) electronic data interchange
Marketing to prospective and established customers by e-mail or fax (for example, with newsletters)
Engaging in pretail for launching new products and services
Online financial exchanges for currency exchanges or trading purposes
कश्मीर (कश्मीरी : कोशूर) भारतीय उपमहाद्वीप का एक हिस्सा है जिसके अलग-अलग भागों पर भारत तथा पाकिस्तान का अधिपत्य है।
ये ख़ूबसूरत भूभाग मुख्यतः झेलम नदी की घाटी (वादी) में बसा है।
यहाँ कई सुन्दर सरोवर हैं, जैसे डल, वुलर और नगीन।
भारतीय कश्मीर घाटी में छः ज़िले हैं :श्रीनगर,बड़ग़ाम,अनन्तनाग,पुलवामा,बारामुला और कुपवाड़ा।
धरती का स्वर्ग कहा जाने वाला कश्मीर ग्रेट हिमालयन रेंज और पीर पंजाल पर्वत श्रृंखला के मध्य स्थित है।
THE HISTORY OF CHINA, as documented in ancient writings, dates back some 3,300 years. Modern archaeological studies provide evidence of still more ancient origins in a culture that flourished between 2500 and 2000 B.C. in what is now central China and the lower Huang He (Yellow River) Valley of north China. Centuries of migration, amalgamation, and development brought about a distinctive system of writing, philosophy, art, and political organization that came to be recognizable as Chinese civilization. What makes the civilization unique in world history is its continuity through over 4,000 years to the present century.
The Chinese have developed a strong sense of their real and mythological origins and have kept voluminous records since very early times. It is largely as a result of these records that knowledge concerning the ancient past, not only of China but also of its neighbors, has survived.
Chinese history, until the twentieth century, was written mostly by members of the ruling scholar-official class and was meant to provide the ruler with precedents to guide or justify his policies. These accounts focused on dynastic politics and colorful court histories and included developments among the commoners only as backdrops. The historians described a Chinese political pattern of dynasties, one following another in a cycle of ascent, achievement, decay, and rebirth under a new family.
Of the consistent traits identified by independent historians, a salient one has been the capacity of the Chinese to absorb the people of surrounding areas into their own civilization. Their success can be attributed to the superiority of their ideographic written language, their technology, and their political institutions; the refinement of their artistic and intellectual creativity; and the sheer weight of their numbers. The process of assimilation continued over the centuries through conquest and colonization until what is now known as China Proper was brought under unified rule. The Chinese also left an enduring mark on people beyond their borders, especially the Koreans, Japanese, and Vietnamese.
Bees sting,but gives us honey.Serpent bites,but it’s poison is used in medicine for treatment of cancer.
Tigers attack,but because of their presence in forests,the poachers dare not to loot,The treasure like skin of deers,tusks of elephants,logs of trees etc.Elephant when gets enraged throws the Mahaut[rider on back] out and tramples the people assembled nearby.But their presence in the temple yard and their participation in procession and cart festival of God adds attraction to the ceremony.Elephants in some forest areas are also used to transport logs of wood.
Crows seize the pieces of bread from the hands of tiny toddlers,But they keep the environment clean by picking worms and rotten things spread around the area.
Spiders web at the corners of the walls look ugly but they catch mosquitoes and flies.Cows and bulls when enraged attack with their horns.But cows give milk and bulls draw carts and plough the fields in rural areas.When the dogs become mad they bite and humans get rabies,But they are homely and faithful in nature.The dog guards the master and his house.Monkeys are a nuisance but the trained ones entertain humans by their aerobatics.Donkeys kick with their hinder legs but they carry loads.Horses are powerful and proud.They are not honest.When humans invest them in races and use them for gambling they may ruin them, if luck fails.But they serve as means of livelihood for the poor who use them to draw carts.Fishing,rearing of hens and pigs in farms also provide employment for the humans.Birds eat the grains in fields but they pick the worms that cause the disease to the plants or burrow the plants.The dancing peacock represents pride.Swan stands for graceful movement,cocky means arrogant,Eagle’s eye represents sharp view,fox represents cunningness and wisdom.
When child learns to speak,we appreciate-” the child speaks like a parrot”.When a lady sings melodiously we appreciate-“she sings like a cuckoo’.Wild boars dug the soil and eat root vegitables like carrot,potatoes etc.Scientists say that they may be used to detect silent bombs buried underground,During second world war in Germany and other places ,where the metal detectors and police dogs have failed to find out.
homographs (words with the same spellings, but different meanings, origins, or pronunciations. There are two large subgroups:
Subgroup 1:These common words have the same spelling and pronunciation, but very different meanings and/or origins.
Subgroup 2:
These words have the same spelling, but different stress. The stress changes for the noun and verb forms of these words.
A circle is a simple shape in Euclidean geometry. It is the set of all points in a plane that are at a given distance from a given point, the center; equivalently it is the curve traced out by a point that moves so that its distance from a given point is constant.
Traditional Dance continued in Mughal period both in the north and in the south. Kathak was a new dance that had developed during this period. But the art was not pursued purely from an aesthetic point of view. Sufism with its religious fervor expressed itself in dance and music that resulted in the Muslims appreciating the music. Khusro was both a singer and a-dancer.
Africa straddles the equator which bestows a rich diversity of wildlife and landscapes on the world's second largest continent. Large predators roam the sweeping savannas among huge herds of grazing herbivores, while apes, monkeys and snakes inhabit its dark, dense forests. Widely regarded as the place where human life originated, Africa is home to many of the world's best loved and most fascinating animals, as well as to some of its most endangered.
Many natural changes are undesirable.It is necessary that these changes are properly controlled . We must study these changes to learn how they are caused and find ways to control them to safe guard ourselves.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
2. -
Levers are one of basic tools that were probably used in prehistoric times. It
is assumed that in ancient Egypt, constructors used the lever to move and
uplift obelisks weighing more than 100 tons.
Lever is a simple machine that makes
work easier to use; it involves moving a
load around a pivot using a minimum
force.
A lever amplifies an input force to
provide a greater output force,which
is said to provide leverage. The levers
are used to lift heavy weight with
least amount of effort.
LEVERS
3. -
Lever – A bar that is free to pivot
around a center point (Changes
direction and/or amount of force).
Fulcrum – The fixed point around
which a lever pivots (fulcrums can
take many shapes).
Effort Force – The force applied
to a machine to cause motion of an
object. (Measured in Newton N)
Resistance Force – The force
exerted by an object due to gravity
or friction. (Measured in Newton N)
Resistance Arm – The part of the
lever on which the resistance force is
exerted.
Effort Arm – The part of the
lever to which the effort force is
applied.
LEVER SYSTEM
4. -PRINCIPLE OF LEVER
The lever is based on the
principle of lever stating that:
"The force pushing upward at
one end of a lever is equal to the
force pushing downward at the
other end times the ratio of the
distance of the two forces from
the pivot point.
The figure illustrates the
principle of the lever.
6. -
In a Class 1 Lever, the pivot
(fulcrum) is between the effort
and the load. In an off-center
type one lever (like a pliers), the
load is larger than the effort, but
is moved through a smaller
distance.
FIRST CLASS LEVER
8. -SECOND-CLASS LEVERS
Second-class levers have the load between
the effort and the fulcrum. A wheelbarrow
is a second-class lever. The wheel’s axle is
the fulcrum, the handles take the effort, and
the load is placed between them. The effort
always travels a greater distance and is less
than the load.
10. -THIRD-CLASS LEVERS
Third-class levers have the effort placed
between the load and the fulcrum. The effort
always travels a shorter distance and must be
greater than the load. A hammer acts as a
third-class lever when it is used to drive in a
nail: the fulcrum is the wrist, the effort is
applied through the hand, and the load is the
resistance of the wood.