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While there are thousands of financial decisions to make over the year and thousands more strategies and actions to consider when it comes time to decide, there is one enemy that keeps most people from making those decisions _ inertia.

Sir Isaac Newton's First Law of Motion explains it all: "an object at rest remains at rest, and an object in motion remains in motion." This law's application to human behavior translates financially to "unless there is a really big threat, there's no need to do anything." This becomes a dangerous law to the health of personal finances.

Many of us are already overwhelmed by the complexities of personal finances that we develop a shield to avoid coming in contact with the thought patterns needed to improve our situation. Last year was an exception when the stock market plunged far enough for many to move and sell stocks. The recovery is showing some of the same motion as more investors are buying as stocks show steady increases. Those who lost their jobs were moved enough to make changes in their budget that could have been made long before.

Even though these movements are enough to solve inertia among our finances, they didn't exactly make things right. For example, conventional stock wisdom is to buy low and sell high but this situation led many to do the opposite.

Where the real success in breaking inertia comes is in taking time to develop a financial plan and strategy in order to not be influenced by widespread actions of others that breeds the "herding" instinct of human behavior. Personal finances are an individual action, not a group action.

Start by developing a budget and make purchasing decisions around it. Then determine how much you can or should invest every month and set up automatic transfers from your checking account to your investment account (this avoids inertia from preventing you from having to think about doing it every month). By putting finances on automatic pilot, we prevent inertia from taking over and helping us avoid missing bill payments or investments.

When it comes to investments, many people invest and forget about it, which can be a good thing for long-term investors. But those investments do need to be watched for changes. Yahoo Finance lets you enter a portfolio of your investments and sends you alerts of changes, such as down or up by a certain percentage. That way you won't let inertia prevent you from following your investments.

Inertia is both a blessing and a curse. It's all in how you use the law to your advantage.

(Dan Serra is a financial planner with Strategic Financial Planning Inc. in Plano, Texas. E-mail him at serrafinance@yahoo.com or visit his Twitter page at www.twitter.com/danserra.)

© 2009, McClatchy-Tribune Information Services.

Visit the McClatchy Washington Bureau on the World Wide Web at www.mcclatchydc.com.

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© 2009, YellowBrix, Inc.

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inertia: 's law finances finance channel

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While there are thousands of financial decisions to make over the year and thousands more strategies and actions to consider when it comes time to decide, there is one enemy that keeps most people from making those decisions _ inertia.

# data[].attributes.attachment_link.readable_text
Inertia is the tendency of objects in motion to stay in motion, and objects at rest to stay at rest, unless a force causes its speed or direction to change. It is one of the fundamental principles in classical physics, and described by Isaac Newton in his first law of motion (also known as The Principle of Inertia). It is one of the primary manifestations of mass, one of the core quantitative properties of physical systems. Newton writes:

LAW I. Every object perseveres in its state of rest, or of uniform motion in a right line, except insofar as it is compelled to change that state by forces impressed thereon.

-  Isaac Newton, Principa, Translation by Cohen and Whitman, 1999

In his 1687 work Philosophiæ Naturalis Principia Mathematica, Newton defined inertia as a force:

DEFINITION III. The vis insita, or innate force of matter, is a power of resisting by which every body, as much as in it lies, endeavours to persevere in its present state, whether it be of rest or of moving uniformly forward in a right line.

Professor John H. Lienhard points out the Mozi - based on a Chinese text from the Warring States period (475-221 BCE) - as having given the first description of inertia. Before the European Renaissance, the prevailing theory of motion in western philosophy was that of Aristotle (335 BCE to 322 BCE). On the surface of the Earth, the inertia property of physical objects is often masked by gravity and the effects of friction and air resistance, both of which tend to decrease the speed of moving objects (commonly to the point of rest). This misled the philosopher Aristotle to believe that objects would move only as long as force was applied to them. Aristotle said that all moving objects (on Earth) eventually come to rest unless an external power (force) continued to move them. Aristotle explained the continued motion of projectiles, after being separated from their projector, as an (itself unexplained) action of the surrounding medium continuing to move the projectile.

Despite its general acceptance, Aristotle's concept of motion was disputed on several occasions by notable philosophers over nearly two millennia. For example, Lucretius (following, presumably, Epicurus) stated that the "default state" of the matter was motion, not stasis (stagnation). In the 6th century, John Philoponus criticized the inconsistency between Aristotle's discussion of projectiles, where the medium keeps projectiles going, and his discussion of the void, where the medium would hinder a body's motion. Philoponus proposed that motion was not maintained by the action of a surrounding medium, but by some property imparted to the object when it was set in motion. Although this was not the modern concept of inertia, for there was still the need for a power to keep a body in motion, it proved a fundamental step in that direction. This view was strongly opposed by Averroes and by many scholastic philosophers who supported Aristotle. However, this view did not go unchallenged in the Islamic world, where Philoponus had several supporters who further developed his ideas.

In the 11th century, Persian polymath Ibn Sina (Avicenna) claimed that a projectile in a vacuum would not stop unless acted upon.

In the 14th century, Jean Buridan rejected the notion that a motion-generating property, which he named impetus, dissipated spontaneously. Buridan's position was that a moving object would be arrested by the resistance of the air and the weight of the body which would oppose its impetus. Buridan also maintained that impetus increased with speed; thus, his initial idea of impetus was similar in many ways to the modern concept of momentum. Despite the obvious similarities to more modern ideas of inertia, Buridan saw his theory as only a modification to Aristotle's basic philosophy, maintaining many other peripatetic views, including the belief that there was still a fundamental difference between an object in motion and an object at rest. Buridan also believed that impetus could be not only linear but also circular in nature, causing objects (such as celestial bodies) to move in a circle. Buridan's theory was followed up by his pupil Albert of Saxony (1316-1390) and the Oxford Calculators, who performed various experiments which further undermined the Aristotelian model. Their work in turn was elaborated by Nicole Oresme who pioneered the practice of illustrating the laws of motion with graphs.

Shortly before Galileo's theory of inertia, Giambattista Benedetti modified the growing theory of impetus to involve linear motion alone:

[Any] portion of corporeal matter which moves by itself when an impetus has been impressed on it by any external motive force has a natural tendency to move on a rectilinear, not a curved, path.

Benedetti cites the motion of a rock in a sling as an example of the inherent linear motion of objects, forced into circular motion.

According to Charles Coulston Gillispie, inertia "entered science as a physical consequence of Descartes' geometrization of space-matter, combined with the immutability of God." The first physicist to completely break away from the Aristotelian model of motion was Isaac Beeckman in 1614. The term "inertia" was first introduced by Johannes Kepler in his Epitome Astronomiae Copernicanae (published in three parts from 1617 to 1621); however, the meaning of Kepler's term (which he derived from the Latin word for "idleness" or "laziness") was not quite the same as its modern interpretation. Kepler defined inertia only in terms of resistance to movement, once again based on the presumption that rest was a natural state which did not need explanation. It was not until the later work of Galileo and Newton unified rest and motion in one principle that the term "inertia" could be applied to these concepts as it is today.

The principle of inertia, as formulated by Aristotle for "motions in a void", includes that a mundane object tends to resist a change in motion. The Aristotelian division of motion into mundane and celestial became increasingly problematic in the face of the conclusions of Nicolaus Copernicus in the 16th century, who argued that the Earth is never at rest, but is actually in constant motion around the Sun.

Isaac Newton, 1689

Galileo Galilei

Galileo, in his further development of the Copernican model, recognized these problems with the then-accepted nature of motion and, at least partially, as a result, included a restatement of Aristotle's description of motion in a void as a basic physical principle:

A body moving on a level surface will continue in the same direction at a constant speed unless disturbed.

Galileo writes that "all external impediments removed, a heavy body on a spherical surface concentric with the earth will maintain itself in that state in which it has been; if placed in a movement towards the west (for example), it will maintain itself in that movement." This notion, which is termed "circular inertia" or "horizontal circular inertia" by historians of science, is a precursor to but is distinct from Newton's notion of rectilinear inertia. For Galileo, a motion is " horizontal" if it does not carry the moving body towards or away from the center of the Earth, and for him, "a ship, for instance, having once received some impetus through the tranquil sea, would move continually around our globe without ever stopping." It is also worth noting that Galileo later (in 1632) concluded that based on this initial premise of inertia, it is impossible to tell the difference between a moving object and a stationary one without some outside reference to compare it against. This observation ultimately came to be the basis for Albert Einstein to develop the theory of special relativity.

Concepts of inertia in Galileo's writings would later come to be refined, modified, and codified by Isaac Newton as the first of his Laws of Motion (first published in Newton's work, Philosophiæ Naturalis Principia Mathematica, in 1687):

Every body perseveres in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed thereon.

Despite having defined the concept in his laws of motion, Newton did not actually use the term "inertia." In fact, originally he viewed the respective phenomenon as being caused by "innate forces" inherent in matter, which resisted any acceleration. Given this perspective, and borrowing from Kepler, Newton attributed the term "inertia" to mean "the innate force possessed by an object which resists changes in motion"; thus, Newton defined "inertia" to mean the cause of the phenomenon, rather than the phenomenon itself. However, Newton's original ideas of "innate resistive force" were ultimately problematic for a variety of reasons, and thus most physicists no longer think in these terms. As no alternate mechanism has been readily accepted, and it is now generally accepted that there may not be one that we can know, the term "inertia" has come to mean simply the phenomenon itself, rather than any inherent mechanism. Thus, ultimately, "inertia" in modern classical physics has come to be a name for the same phenomenon as described by Newton's First Law of Motion, and the two concepts are now considered to be equivalent.

The effect of inertial mass: if pulled slowly, the upper thread breaks (a). If pulled quickly, the lower thread breaks (b).

Albert Einstein's theory of special relativity, as proposed in his 1905 paper entitled " On the Electrodynamics of Moving Bodies", was built on the understanding of inertial reference frames developed by Galileo, Huygens and Newton. While this revolutionary theory did significantly change the meaning of many Newtonian concepts such as mass, energy, and distance, Einstein's concept of inertia remained at first unchanged from Newton's original meaning. However, this resulted in a limitation inherent in special relativity: the principle of relativity could only apply to inertial reference frames. To address this limitation, Einstein developed his general theory of relativity ("The Foundation of the General Theory of Relativity", 1916), which provided a theory including noninertial (accelerated) reference frames.

In general relativity, the concept of inertial motion got a broader meaning. Taking into account general relativity, inertial motion is any movement of a body that is not affected by forces of electrical, magnetic, or other origin, but that is only under the influence of gravitational masses. Physically speaking, this happens to be exactly what a properly functioning three-axis accelerometer is indicating when it does not detect any proper acceleration.

The term inertia comes from the Latin word iners, meaning idle or sluggish.

Rotational inertia

A quantity related to inertia is rotational inertia (→ moment of inertia), the property that a rotating rigid body maintains its state of uniform rotational motion. Its angular momentum remains unchanged unless an external torque is applied; this is called conservation of angular momentum. Rotational inertia is often considered in relation to a rigid body. For example, a gyroscope uses the property that it resists any change in the axis of rotation.

1. ^ Aristotle: Minor works (1936), Mechanical Problems (Mechanica), University of Chicago Library: Loeb Classical Library Cambridge (Mass.) and London, p. 407, ...it [a body] stops when the force which is pushing the travelling object has no longer power to push it along...

2. Pages 2 to 4, Section 1.1, ^ "Skating", Chapter 1, "Things that Move", Louis Bloomfield, Professor of Physics at the University of Virginia, How Everything Works: Making Physics Out of the Ordinary, John Wiley & Sons (2007), hardcover, ISBN 978-0-471-74817-5

3. Aristotle, ^ Physics, 8.10, 267a1-21; Aristotle, Physics, trans. by R. P. Hardie and R. K. Gaye, 'projectile' Archived 2007-01-29 at the Wayback Machine.

4. Espinoza, Fernando. "An Analysis of the Historical Development of Ideas About Motion and its Implications for Teaching". Physics Education. Vol. 40(2). ^ Medieval thought.

5. Jean Buridan: Quaestiones on Aristotle's Physics (quoted at ^ Impetus Theory)

6. ^ Gillispie, Charles Coulston (1960). The Edge of Objectivity: An Essay in the History of Scientific Ideas. Princeton University Press. pp. 367-68. ISBN 0-691-02350-6.

7. Lawrence Nolan (ed.), ^ The Cambridge Descartes Lexicon, Cambridge University Press, 2016, "Inertia.", p. 405

8. See Alan Chalmers article "Galilean Relativity and Galileo's Relativity", in ^ Correspondence, Invariance and Heuristics: Essays in Honour of Heinz Post, eds. Steven French and Harmke Kamminga, Kluwer Academic Publishers, Dordrecht, 1991, pp. 199-200, ISBN 0792320859. Chalmers does not, however, believe that Galileo's physics had a general principle of inertia, circular or otherwise. page 199

9. Dijksterhuis E.J. ^ The Mechanisation of the World Picture, Oxford University Press, Oxford, 1961, p. 352

10. According to Newtonian mechanics, if a projectile on a smooth spherical planet is given an initial horizontal velocity, it will not remain on the surface of the planet. Various curves are possible depending on the initial speed and the height of the launch. See Harris Benson ^ University Physics, New York 1991, page 268. If constrained to remain on the surface, by being sandwiched, say, in between two concentric spheres, it will follow a great circle on the surface of the earth, i.e. will only maintain a westerly direction if fired along the equator. See "Using great circles" Using great circles

11. Alfred Engel English Translation:^ Einstein, Albert (1997), The Foundation of the General Theory of Relativity (PDF), New Jersey: Princeton University Press

12. ^ Max Born (1922). "Einstein's Theory of Relativity - inertial motion, p. 252". New York, E. P. Dutton and company, publishers.

Butterfield, H (1957), The Origins of Modern Science, ISBN 0-7135-0160-X.

Clement, J (1982), "Students' preconceptions in introductory mechanics", American Journal of Physics vol 50, pp 66-71

Crombie, A C (1959), Medieval and Early Modern Science, vol. 2.

McCloskey, M (1983), "Intuitive physics", Scientific American, April, pp. 114-123.

McCloskey, M & Carmazza, A (1980), "Curvilinear motion in the absence of external forces: naïve beliefs about the motion of objects", Science vol. 210, pp. 1139-1141.

Pfister, Herbert; King, Markus (2015). Inertia and Gravitation. The Fundamental Nature and Structure of Space-Time. Vol. The Lecture Notes in Physics. Volume 897. Heidelberg: Springer. doi:10.1007/978-3-319-15036-9. ISBN 978-3-319-15035-2.

Ragep, F. Jamil (2001a). "Tusi and Copernicus: The Earth's Motion in Context". Science in Context. Cambridge University Press. 14 (1-2): 145-163. doi:10.1017/S0269889701000060. S2CID 145372613.

Ragep, F. Jamil (2001b). "Freeing Astronomy from Philosophy: An Aspect of Islamic Influence on Science". Osiris. 2nd Series. 16 (Science in Theistic Contexts: Cognitive Dimensions): 49-64 & 66-71. Bibcode:2001Osir...16...49R. doi:10.1086/649338. S2CID 142586786.

# data[].attributes.attachment_link.description
Inertia is the tendency of objects in motion to stay in motion, and objects at rest to stay at rest, unless a force causes its speed or direction to change. It is one of the fundamental principles in classical physics, and described by Isaac Newton in his first law of motion (also known as The Principle of Inertia).

# data[].attributes.attachment_link.readable_text
Inertia is the tendency of objects in motion to stay in motion, and objects at rest to stay at rest, unless a force causes its speed or direction to change. It is one of the fundamental principles in classical physics, and described by Isaac Newton in his first law of motion (also known as The Principle of Inertia). It is one of the primary manifestations of mass, one of the core quantitative properties of physical systems. Newton writes:

LAW I. Every object perseveres in its state of rest, or of uniform motion in a right line, except insofar as it is compelled to change that state by forces impressed thereon.

-  Isaac Newton, Principa, Translation by Cohen and Whitman, 1999

In his 1687 work Philosophiæ Naturalis Principia Mathematica, Newton defined inertia as a force:

DEFINITION III. The vis insita, or innate force of matter, is a power of resisting by which every body, as much as in it lies, endeavours to persevere in its present state, whether it be of rest or of moving uniformly forward in a right line.

Professor John H. Lienhard points out the Mozi - based on a Chinese text from the Warring States period (475-221 BCE) - as having given the first description of inertia. Before the European Renaissance, the prevailing theory of motion in western philosophy was that of Aristotle (335 BCE to 322 BCE). On the surface of the Earth, the inertia property of physical objects is often masked by gravity and the effects of friction and air resistance, both of which tend to decrease the speed of moving objects (commonly to the point of rest). This misled the philosopher Aristotle to believe that objects would move only as long as force was applied to them. Aristotle said that all moving objects (on Earth) eventually come to rest unless an external power (force) continued to move them. Aristotle explained the continued motion of projectiles, after being separated from their projector, as an (itself unexplained) action of the surrounding medium continuing to move the projectile.

Despite its general acceptance, Aristotle's concept of motion was disputed on several occasions by notable philosophers over nearly two millennia. For example, Lucretius (following, presumably, Epicurus) stated that the "default state" of the matter was motion, not stasis (stagnation). In the 6th century, John Philoponus criticized the inconsistency between Aristotle's discussion of projectiles, where the medium keeps projectiles going, and his discussion of the void, where the medium would hinder a body's motion. Philoponus proposed that motion was not maintained by the action of a surrounding medium, but by some property imparted to the object when it was set in motion. Although this was not the modern concept of inertia, for there was still the need for a power to keep a body in motion, it proved a fundamental step in that direction. This view was strongly opposed by Averroes and by many scholastic philosophers who supported Aristotle. However, this view did not go unchallenged in the Islamic world, where Philoponus had several supporters who further developed his ideas.

In the 11th century, Persian polymath Ibn Sina (Avicenna) claimed that a projectile in a vacuum would not stop unless acted upon.

In the 14th century, Jean Buridan rejected the notion that a motion-generating property, which he named impetus, dissipated spontaneously. Buridan's position was that a moving object would be arrested by the resistance of the air and the weight of the body which would oppose its impetus. Buridan also maintained that impetus increased with speed; thus, his initial idea of impetus was similar in many ways to the modern concept of momentum. Despite the obvious similarities to more modern ideas of inertia, Buridan saw his theory as only a modification to Aristotle's basic philosophy, maintaining many other peripatetic views, including the belief that there was still a fundamental difference between an object in motion and an object at rest. Buridan also believed that impetus could be not only linear but also circular in nature, causing objects (such as celestial bodies) to move in a circle. Buridan's theory was followed up by his pupil Albert of Saxony (1316-1390) and the Oxford Calculators, who performed various experiments which further undermined the Aristotelian model. Their work in turn was elaborated by Nicole Oresme who pioneered the practice of illustrating the laws of motion with graphs.

Shortly before Galileo's theory of inertia, Giambattista Benedetti modified the growing theory of impetus to involve linear motion alone:

[Any] portion of corporeal matter which moves by itself when an impetus has been impressed on it by any external motive force has a natural tendency to move on a rectilinear, not a curved, path.

Benedetti cites the motion of a rock in a sling as an example of the inherent linear motion of objects, forced into circular motion.

According to Charles Coulston Gillispie, inertia "entered science as a physical consequence of Descartes' geometrization of space-matter, combined with the immutability of God." The first physicist to completely break away from the Aristotelian model of motion was Isaac Beeckman in 1614. The term "inertia" was first introduced by Johannes Kepler in his Epitome Astronomiae Copernicanae (published in three parts from 1617 to 1621); however, the meaning of Kepler's term (which he derived from the Latin word for "idleness" or "laziness") was not quite the same as its modern interpretation. Kepler defined inertia only in terms of resistance to movement, once again based on the presumption that rest was a natural state which did not need explanation. It was not until the later work of Galileo and Newton unified rest and motion in one principle that the term "inertia" could be applied to these concepts as it is today.

The principle of inertia, as formulated by Aristotle for "motions in a void", includes that a mundane object tends to resist a change in motion. The Aristotelian division of motion into mundane and celestial became increasingly problematic in the face of the conclusions of Nicolaus Copernicus in the 16th century, who argued that the Earth is never at rest, but is actually in constant motion around the Sun.

Isaac Newton, 1689

Galileo Galilei

Galileo, in his further development of the Copernican model, recognized these problems with the then-accepted nature of motion and, at least partially, as a result, included a restatement of Aristotle's description of motion in a void as a basic physical principle:

A body moving on a level surface will continue in the same direction at a constant speed unless disturbed.

Galileo writes that "all external impediments removed, a heavy body on a spherical surface concentric with the earth will maintain itself in that state in which it has been; if placed in a movement towards the west (for example), it will maintain itself in that movement." This notion, which is termed "circular inertia" or "horizontal circular inertia" by historians of science, is a precursor to but is distinct from Newton's notion of rectilinear inertia. For Galileo, a motion is " horizontal" if it does not carry the moving body towards or away from the center of the Earth, and for him, "a ship, for instance, having once received some impetus through the tranquil sea, would move continually around our globe without ever stopping." It is also worth noting that Galileo later (in 1632) concluded that based on this initial premise of inertia, it is impossible to tell the difference between a moving object and a stationary one without some outside reference to compare it against. This observation ultimately came to be the basis for Albert Einstein to develop the theory of special relativity.

Concepts of inertia in Galileo's writings would later come to be refined, modified, and codified by Isaac Newton as the first of his Laws of Motion (first published in Newton's work, Philosophiæ Naturalis Principia Mathematica, in 1687):

Every body perseveres in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed thereon.

Despite having defined the concept in his laws of motion, Newton did not actually use the term "inertia." In fact, originally he viewed the respective phenomenon as being caused by "innate forces" inherent in matter, which resisted any acceleration. Given this perspective, and borrowing from Kepler, Newton attributed the term "inertia" to mean "the innate force possessed by an object which resists changes in motion"; thus, Newton defined "inertia" to mean the cause of the phenomenon, rather than the phenomenon itself. However, Newton's original ideas of "innate resistive force" were ultimately problematic for a variety of reasons, and thus most physicists no longer think in these terms. As no alternate mechanism has been readily accepted, and it is now generally accepted that there may not be one that we can know, the term "inertia" has come to mean simply the phenomenon itself, rather than any inherent mechanism. Thus, ultimately, "inertia" in modern classical physics has come to be a name for the same phenomenon as described by Newton's First Law of Motion, and the two concepts are now considered to be equivalent.

The effect of inertial mass: if pulled slowly, the upper thread breaks (a). If pulled quickly, the lower thread breaks (b).

Albert Einstein's theory of special relativity, as proposed in his 1905 paper entitled " On the Electrodynamics of Moving Bodies", was built on the understanding of inertial reference frames developed by Galileo, Huygens and Newton. While this revolutionary theory did significantly change the meaning of many Newtonian concepts such as mass, energy, and distance, Einstein's concept of inertia remained at first unchanged from Newton's original meaning. However, this resulted in a limitation inherent in special relativity: the principle of relativity could only apply to inertial reference frames. To address this limitation, Einstein developed his general theory of relativity ("The Foundation of the General Theory of Relativity", 1916), which provided a theory including noninertial (accelerated) reference frames.

In general relativity, the concept of inertial motion got a broader meaning. Taking into account general relativity, inertial motion is any movement of a body that is not affected by forces of electrical, magnetic, or other origin, but that is only under the influence of gravitational masses. Physically speaking, this happens to be exactly what a properly functioning three-axis accelerometer is indicating when it does not detect any proper acceleration.

The term inertia comes from the Latin word iners, meaning idle or sluggish.

Rotational inertia

A quantity related to inertia is rotational inertia (→ moment of inertia), the property that a rotating rigid body maintains its state of uniform rotational motion. Its angular momentum remains unchanged unless an external torque is applied; this is called conservation of angular momentum. Rotational inertia is often considered in relation to a rigid body. For example, a gyroscope uses the property that it resists any change in the axis of rotation.

1. ^ Aristotle: Minor works (1936), Mechanical Problems (Mechanica), University of Chicago Library: Loeb Classical Library Cambridge (Mass.) and London, p. 407, ...it [a body] stops when the force which is pushing the travelling object has no longer power to push it along...

2. Pages 2 to 4, Section 1.1, ^ "Skating", Chapter 1, "Things that Move", Louis Bloomfield, Professor of Physics at the University of Virginia, How Everything Works: Making Physics Out of the Ordinary, John Wiley & Sons (2007), hardcover, ISBN 978-0-471-74817-5

3. Aristotle, ^ Physics, 8.10, 267a1-21; Aristotle, Physics, trans. by R. P. Hardie and R. K. Gaye, 'projectile' Archived 2007-01-29 at the Wayback Machine.

4. Espinoza, Fernando. "An Analysis of the Historical Development of Ideas About Motion and its Implications for Teaching". Physics Education. Vol. 40(2). ^ Medieval thought.

5. Jean Buridan: Quaestiones on Aristotle's Physics (quoted at ^ Impetus Theory)

6. ^ Gillispie, Charles Coulston (1960). The Edge of Objectivity: An Essay in the History of Scientific Ideas. Princeton University Press. pp. 367-68. ISBN 0-691-02350-6.

7. Lawrence Nolan (ed.), ^ The Cambridge Descartes Lexicon, Cambridge University Press, 2016, "Inertia.", p. 405

8. See Alan Chalmers article "Galilean Relativity and Galileo's Relativity", in ^ Correspondence, Invariance and Heuristics: Essays in Honour of Heinz Post, eds. Steven French and Harmke Kamminga, Kluwer Academic Publishers, Dordrecht, 1991, pp. 199-200, ISBN 0792320859. Chalmers does not, however, believe that Galileo's physics had a general principle of inertia, circular or otherwise. page 199

9. Dijksterhuis E.J. ^ The Mechanisation of the World Picture, Oxford University Press, Oxford, 1961, p. 352

10. According to Newtonian mechanics, if a projectile on a smooth spherical planet is given an initial horizontal velocity, it will not remain on the surface of the planet. Various curves are possible depending on the initial speed and the height of the launch. See Harris Benson ^ University Physics, New York 1991, page 268. If constrained to remain on the surface, by being sandwiched, say, in between two concentric spheres, it will follow a great circle on the surface of the earth, i.e. will only maintain a westerly direction if fired along the equator. See "Using great circles" Using great circles

11. Alfred Engel English Translation:^ Einstein, Albert (1997), The Foundation of the General Theory of Relativity (PDF), New Jersey: Princeton University Press

12. ^ Max Born (1922). "Einstein's Theory of Relativity - inertial motion, p. 252". New York, E. P. Dutton and company, publishers.

Butterfield, H (1957), The Origins of Modern Science, ISBN 0-7135-0160-X.

Clement, J (1982), "Students' preconceptions in introductory mechanics", American Journal of Physics vol 50, pp 66-71

Crombie, A C (1959), Medieval and Early Modern Science, vol. 2.

McCloskey, M (1983), "Intuitive physics", Scientific American, April, pp. 114-123.

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Inertia is the tendency of objects in motion to stay in motion, and objects at rest to stay at rest, unless a force causes its speed or direction to change. It is one of the fundamental principles in classical physics, and described by Isaac Newton in his first law of motion (also known as The Principle of Inertia).

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INERTIA is the latin root for lazy like jalen

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Inertia is an object at motion stays at motion or an object at rest stays at rest.

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Inertia is the latin word for laziness.

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inertia is a word for lazy in latin

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example of  inertia is a rock not moving or just really lazy or doesn't wont to move

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Inertia is the law that objects in motion stay in motion, and objects at rest stay at rest, unless acted upon by an outside force

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laziness in latin

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it is the latin root for lazy

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An example of Inertia is a stone, if the stone is moved in space, it will forever move, but if it is sitting and nothing moves it, it will always stay sitting.

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Inertia is the Latin root for laziness. and it stands for how when something starts moving it would want to keep moving but when it is at stop it is hard for it to move again. But once it is at motion it will only stop if something gets in the objects way.

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inertia is the Latin word for laziness. A example of inertia is a ball rolling down a hill and nothing is going to stop it then another force has to stop it.

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An example is if there is nothing to stop an object, it will keep on moving.

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Inertia is the Latin word for laziness. It also means things at rest stays at rest.

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Inertia Latin word for "Laziness. A example could be

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Inertia is the latin word for "laziness" and it technically means that once a object stays it just wants to stay especially at rest. And in order to move an object you have to use force. For example in order to move a soccer ball or a basketball you have to put your best effort to push or pull the ball.

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Inertia is when an object is in motion it stays in motion and when an object is at rest, the object will stay at rest.

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inetia is a latin word for laziness an example is me

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inertia is the stop or go of an object,

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Inertia is latin word for laziness

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Inertia is a tendency to do nothing or to remain unchanged.

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Inertia is a tendency to do nothing or to remain unchanged. Latin root for laziness.

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Inertia is Newton's first law of motion, stating that an object in motion stays in motion, and an object at rest stays at rest, unless acted upon by an outside force. An example of inertia is when there is a large boulder that is difficult to move, and can only be moved by an opposing force. This is because of inertia, the Latin word for "laziness".

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Inertia is the Latin root for 'laziness'. Inertia explains things at rest want to stay at rest. It also elaborates that things in motion stay in motion. It takes effort to move something. An example of inertia is a ball. You move the ball by using force or else it stays where it is.

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Inertia is the Latin word for laziness in Latin, and the law that says that things in motion stay in motion, and things at rest stay at rest.