subatomiconsciousness:

Newton’s laws of motions 

First law of motion

An object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.This law is often called “the law of inertia”

This means that there is a natural tendency of objects to keep on doing what they’re doing. All objects resist changes in their state of motion. In the absence of an unbalanced force, an object in motion will maintain this state of motion.

2cnd law of motion

Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object).

Everyone unconsciously knows the Second Law. Everyone knows that heavier objects require more force to move the same distance as lighter objects.

3rd law of motion

For every action there is an equal and opposite re-action.

This means that for every force there is a reaction force that is equal in size, but opposite in direction. That is to say that whenever an object pushes another object it gets pushed back in the opposite direction equally hard. 

this video & here

(via likeaphysicist)

Mathematical Principles of Natural Philosophy by Isaac Newton

(via blackholecosmos)

Astronomers Measure Sunlight’s Shove

The physical force of sunlight on a moving asteroid has been measured by NASA scientists, providing information on how to better plot these Earth-passing worlds’ future paths.

First proposed by a 19-century Russian engineer, the Yarkovsky effect is the result of an object in space absorbing radiation from the Sun and emitting it as heat, thus creating a slight-but-measurable change in its movement (thanks to Newton’s first law of motion.)

By observing the 1999, 2005 and 2011 close passes of asteroid 1999 RQ36 with theArecibo and Goldstone radar telescopes, astronomers were able to determine how much the trajectory of the half-kilometer-wide asteroid had changed.

The researchers’ findings revealed that RQ36 shifted by 160 km – about 100 miles – over the course of those 12 years. That deviation is attributed to the Yarkovsky effect. A miniscule force in and of itself, over time it has the ability to move entire worlds (albeit relatively small ones.)

“The Yarkovsky force on 1999 RQ36 at its peak, when the asteroid is nearest the Sun, is only about a half ounce — about the weight of three grapes on Earth,” said Steven Chesley of NASA’s Jet Propulsion Laboratory in Pasadena “Meanwhile, the mass of the asteroid is estimated to be about 68 million tons. You need extremely precise measurements over a fairly long time span to see something so slight acting on something so huge.”

Using measurements of the distance between the Arecibo Observatory in Puerto Rico and RQ36 during its latest pass in 2011 – a feat that was compared by team leader Michael Nolan to “measuring the distance between New York City and Los Angeles to an accuracy of two inches” – Chesley and his team were able to calculate all the asteroid’s near-Earth approaches closer than 7.5 million km (4.6 million miles) from the years 1654 to 2135. 11 such passes were found.

In addition, observation of 1999 RQ36 with NASA’s Spitzer Space Telescope found it to have about the same density as water – that’s light, for an asteroid.

Most likely, RQ36 is a “rubble-pile” form of asteroid, composed of a conglomeration of individual chunks of material held together by gravity.

These findings will be used by NASA scientists to help fine-tune the upcomingOSIRIS-REx mission, which is scheduled to launch in 2016 to rendezvous with 1999 RQ36 and return samples to Earth in 2023. Being a loose collection of rocks is expected to aid in the spacecraft’s sample retrieval process.

The findings were presented on May 19 at the Asteroids, Comets and Meteors 2012 meeting in Niigata, Japan. Read more here.

(Top image: series of radar images of asteroid 1999 RQ36 were obtained by NASA’s Deep Space Network antenna in Goldstone, Calif. on Sept 23, 1999. Credit: NASA/JPL-Caltech)

quantumaniac:

Isaac Newton Fun Facts

Isaac Newton (1642-1727) was without a doubt one of the most important scientists of all time, if not the most important. Here are some fun facts about ol’ Ike: 

• Newton became a professor of mathematics at only 26.
• Newton practiced Alchemy. 
• Newton was elected as a member of parliment. His membership lasted only a year.
• Newton earned the title of Warden of the Royal Mint.
• Newton oversaw the recoinage of the whole country.
• Newton was knighted because of his political activites.
• He was named after his father who died three months before Isaac was born.
• Isaac was born early. He was so small he could have put him in a quart jug.
• Isaac’s father could hardly write his name.
• Isaac was one of the worst in his class until a bully at school kicked him. Isaac challenged him to a fight even though he was smaller. He won. That wasn’t enough for him, he decided to be better than the bully at school as well.
• Isaac liked to draw, his room was even colored on the ceilings and walls.
• Newton was born on Christmas.

rhamphotheca:

The Fish That Nearly Sank Isaac Newton’s Career

by Stephanie Pappas

An intricate image of a flying fish is one of hundreds of images now searchable online courtesy of the Royal Society, the United Kingdom’s national academy of science.

This striking wood engraving appeared in the 1686 text “Historia Piscium” or “The History of Fishes” by John Ray and Francis Willughby. Now mostly forgotten, the book was groundbreaking for its time. Unfortunately, “The History of Fishes” almost prevented another groundbreaking work from being published: Isaac Newton’s “Philosophiae Naturalis Principia Mathematica” (“Mathematical Principles of Natural Philosophy”).

The lavish engravings in “The History of Fishes” were so expensive to publish that they nearly bankrupted the young Royal Society, at that time only 26 years old. Short of cash, the Society had to rescind its promise to help pay for the production of Newton’s masterpiece.

Fortunately for Newton (and for science), his “Principia” caught astronomer Edmond Halley’s eye. Halley would be remembered mainly for computing the orbit of the comet that bears his name, but at the time he was a young Royal Society clerk. Halley took on the “Principia” as a personal project, raising funds (many from his own pocket) to get the work published in 1687…

(read more: Live Science)    

(image: John Ray and Francis Willughby, 1686, courtesy of the Royal Society)

(via scinerds)

“There is a popular misconception that science is an impersonal, dispassionate, and thoroughly objective enterprise. Whereas most other human activities are dominated by fashions, fads, and personalities, science is supposed to be constrained by agreed rules of procedure and rigorous tests. It is the results that count, not the people who produce them.

This is, of course, manifest nonsense.

Science is a people-driven activity like all human endeavor, and just as subject to fashion and whim. In this case fashion is set not so much by choice of subject matter, but by the way scientists think about the world. Each age adopts its particular approach to scientific problems, usually following the trail blazed by certain dominant figures who both set the agenda and define the best methods to tackle it.

Occasionally scientists attain sufficient stature that they become noticed by the general public, and when endowed with outstanding flair a scientist may become an icon for the entire scientific community.

In earlier centuries Isaac Newton was an icon. Newton personified the gentleman scientist - well connected, devoutly religious, unhurried, and methodical in his work. His style of doing science set the standard for two hundred years.

In the first half of the twentieth century Albert Einstein replaced Newton as the popular scientist icon. Eccentric, dishevelled, Germanic, absent-minded, utterly absorbed in his work, and an archetypal abstract thinker, Einstein changed the way physics is done by questioning the very concepts that define the subject.

Richard Feynman has become an icon for late twentieth-century existing formalisms and developing his own highly intuitive approach. Whereas most theoretical physicists rely on careful methematical calculation to provide a guide and a crutch to take them into unfamiliar territory, Feynman’s attitude was almost cavalier. You get the impression that he could read nature like a book and simply report on what he found, without the tedium of complex analysis.”