Newton's first law of motion

 

Newton's first law of motion

What is Newton's first law of motion?

Newton's first law of motion states an object at rest or in motion will remain at rest or in motion unless acted upon by an unbalanced force. A ball will continue to move in the forward direction unless an unbalanced force acts on it.

What are the 3 laws of motion?

Newtons's first law of motion states an object at rest or in motion will remain at rest or in motion unless acted upon by an unbalanced force. Newton's second law of motion states the net force (F_{net}) of an object is dependent on both the mass (m) and acceleration (a) of an object. Newton's third law of motion states for every action, there is an equal and opposite reaction.

What are examples of Newton's 1st law of motion?

According to Newton's first law of motion; if a pan full of water was carried around a track, the water would tend to remain traveling forward. However, as the water moves to the left, the water will appear to splash to the right. Space is almost a perfect vacuum void of matter and gravity. Consider a satellite orbiting Earth at 17,500 mph. If a rock were released from the satellite, the rock would orbit earth at a velocity of 17,500 mph next to the satellite.

In 1687 English scientist Sir Isaac Newton published his three laws of motion. Newton's laws of motion are relatively simple statements that revolutionized humanity's understanding of the physical world. Today they are considered foundational to classical mechanics, one of the main branches of physics.

A simple definition of Newton's first law of motion is that it is a law of physics that states that an object at rest or in motion will remain at rest or in motion unless acted upon by an unbalanced force. A force is a push or pull on an object with mass that causes a change in the object's motion. Force is measured in Newtons (N) or kg m/s^{2}.

Balanced Force

The image below shows forces directly acting on the box. Since the magnitude of the arrows are equal, the upward and downward forces are balanced. Balanced forces are equal in magnitude and opposite direction. According to Newton's first law, balanced forces are responsible for keeping an object at rest or maintaining an object's constant velocity.

Inertia is directly proportional to mass. The greater the mass an object has the more the object will resist a change in motion. The elephants in this image have different masses. If these elephants were running at the same speed and had to stop immediately, the more massive elephants would resist changes to their forward state of motion more than the less massive elephants. Thus, according to Newton's first law of motion, the more massive elephants are said to have greater inertia.

Law of Conservation of Matter

 

Law of Conservation of Matter

What is conservation of mass?

The law of conservation of mass states that, during processes like chemical reactions, matter can neither be created nor destroyed.

What is an example of conservation of matter?

A common example of the law of conservation of matter is the reaction of baking soda and vinegar. At first glance, the reaction seems to finish with less mass than it started with. But by placing a balloon atop the reaction container, one can see that the lost mass is actually due to the creation of a gas called carbon dioxide.

What does the law of conservation of matter state?

The law of conservation of matter states that no matter can ever be created or destroyed. Chemical reactions simply rearrange atoms to form new compounds.

he law of conservation of matter, also know as "the law of conservation of mass," states that matter can neither be created nor destroyed. The law's modern form stems from Antoine Lavoisier's work with chemical reactions in the late 18th century. It replaced the phlogiston theory, which stated that mass was destroyed during combustion processes.

Lavoisier's new theory, along with the work of countless other scientists, helped lay the groundwork for the discovery of the chemical elements and, eventually, the periodic table. It has now been so thoroughly tested and is so universally accepted, that it is considered a scientific law.

Matter is defined as physical material that occupies space and possesses mass. The phlogiston theory, which had a very long history, was built upon the observation that fuel loses mass as it burns. This is a correct observation: after you burn a piece of wood, the wood has less mass than it did prior to burning. But the phlogiston theory did not take into account the escape of gases. Burning wood releases carbon dioxide, water vapor, and aerosols. The weighing of these gases was impossible until the invention of the vacuum pump in the 17th century. This invention allowed scientists to weigh gases and to eventually prove that mass was not destroyed during combustion processes. Rather, the mass is simply transformed into gases.

This conclusion is essentially true with all chemical reactions. In all cases, atoms are not created or destroyed; they are simply broken apart, rearranged, or put together in new ways. Of course, these new resulting combinations of atoms can form very new, very different substances. But the mass of the atoms before the reaction and the mass of the atoms after the reaction are always equal.

Modern exceptions to this law have been made to allow for nuclear processes, including fusion, fission, and matter-antimatter reactions. In these cases, mass can be converted into energy and vice versa. 

For chemists, the implications of this law are many. First, the law allowed for chemical reactions to be fully understood and fully quantified. Previously ignored chemical substances (like carbon dioxide being released from a fire) were studied and measured.

The law also allows scientists to predict the mass of the products in a chemical reaction. This can be vital in a variety of situations. Rocket fuel, for example, is specifically formulated with the right ratio of kerosene and liquid oxygen so that it burns fully and completely. Knowing the mass of the two products being burned allows scientists to predict exactly how carbon dioxide and water vapor will be produced. From there, scientists can estimate the mass and velocity of the exhaust gases and predict the amount of thrust that a rocket engine will provide.

The Difference Between Travel and Tourism

 The Difference Between Travel and Tourism

What is the difference between travel and tourism? In short, travel describes a broad activity, and tourism is part of it. This doesn’t mean they are the same, because not all travel is tourism. 

According to Merriam-Webster, tourism describes the practice of traveling for recreation and the guidance or management of tourists. People in a place that is traveled to will set up businesses like hotels, tour companies, and more, to support visitors, creating a tourism industry.

The term travel means “to go on a trip or a tour.” This could include traveling for tourism, but it could also include business travel, travel to visit family, travel for immigration, and other reasons. There are plenty of reasons to travel that don’t involve tourism.  

The difference between travel and tourism is subtle, but it’s there! And it’s important to note it before we unpack the differences between travelers and tourists.

Tourist vs. Traveler: What’s the Difference?

It’s hard to unpack the differences between tourists and travelers because there’s both a perceived definition of these words (this is what we see talked about online) and there’s the formal, dictionary definition. 

Perceived Differences Between Tourist and Traveler

These words are often used to evoke two specific images of a person who travels. The “traveler” is portrayed as someone who is intrepid and goes to less mainstream places. Whereas a “tourist” is wandering around with a guidebook in their hands, going to well-known sights. 

This creates a binary where a “tourist” is one thing, different from a “traveler.”

I don’t think these descriptions are totally fair. There is much more nuance involved, because a tourist can be a mixture of these descriptions, and, participating in “tourist” activities isn’t always a bad thing. 

Official Definitions of Tourist and Traveler

I’ve listed the common perceived ideas around tourist vs. traveler. But what are the official definitions? 

Merriam Webster dictionary defines a tourist as “one that makes a tour for pleasure or culture,” and a traveler as “one that goes on a trip or journey.” 

According to the Oxford English Dictionary, a tourist is “a person who travels for pleasure,” and a traveler is “a person who is traveling or who often travels.”

By these definitions, there really isn’t much of a distinction between the two. Both words refer to the act of traveling to another location. The main distinction between them is that the definition of “tourist” includes the “why” behind that traveling: for pleasure or for culture. 

That distinction (the “why”) is noted in the definition for tourist, but that doesn’t mean it can’t apply to the traveler as well. Anyone who goes on a trip or journey is going to have a “why” – they are heading out on a trip for pleasure, or for culture, or for both.

So, is there a difference between travel and tourism? Yes, but the difference is subtle. Tourism is a part of travel, but not all travel participates in tourism. Given this, you can definitely argue that “traveler” describes people traveling for a variety of reasons, from business travel to immigration. Whereas a tourist is traveling specifically for the experience of tourism, and leisure. 

The way that the tourist vs. traveler binary is used by some to suggest that some tourists do travel better than others isn’t really accurate. It’s okay to be a tourist. When you look at the pros and cons of tourism, simply being a tourist does contribute toward a positive impact when we travel.

That said, a lot of the perceptions of what a “traveler” is point to responsible travel practices that we should all be learning about and trying our best to do. 

The tourist vs. traveler binary contributes to a superiority complex that seems rooted in a sense of competition. And that competition is focused on an individual’s personal “travel identity.”

Rather than focusing on being a traveler vs. a tourist, I think we can all shift our focus instead on putting conscious effort toward promoting and participating in responsible tourism. 

Traveling in a way that leads to more engagement with local life is absolutely something we all should be talking about, learning about and practicing. But let’s do it so that our travel has a better impact on the world – Not so that we can claim we’re one type of traveler over another. 

 

Tourist VS Traveller 

The study of electricity and magnetism

 

The study of electricity and magnetism

Although conceived of as distinct phenomena until the 19th century, electricity and magnetism are now known to be components of the unified field of electromagnetism. Particles with electric charge interact by an electric force, while charged particles in motion produce and respond to magnetic forces as well. Many subatomic particles, including the electrically charged electron and proton and the electrically neutral neutron, behave like elementary magnets. On the other hand, in spite of systematic searches undertaken, no magnetic monopoles, which would be the magnetic analogues of electric charges, have ever been found.

The field concept plays a central role in the classical formulation of electromagnetism, as well as in many other areas of classical and contemporary physics. Einstein’s gravitational field, for example, replaces Newton’s concept of gravitational action at a distance. The field describing the electric force between a pair of charged particles works in the following manner: each particle creates an electric field in the space surrounding it, and so also at the position occupied by the other particle; each particle responds to the force exerted upon it by the electric field at its own position.

 

types of electromagnetic radiation

Radio waves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays are all types of electromagnetic radiation. Radio waves have the longest wavelength, and gamma rays have the shortest wavelength.(more)

Classical electromagnetism is summarized by the laws of action of electric and magnetic fields upon electric charges and upon magnets and by four remarkable equations formulated in the latter part of the 19th century by the Scottish physicist James Clerk Maxwell. The latter equations describe the manner in which electric charges and currents produce electric and magnetic fields, as well as the manner in which changing magnetic fields produce electric fields, and vice versa. From these relations Maxwell inferred the existence of electromagnetic waves—associated electric and magnetic fields in space, detached from the charges that created them, traveling at the speed of light, and endowed with such “mechanical” properties as energy, momentum, and angular momentum. The light to which the human eye is sensitive is but one small segment of an electromagnetic spectrum that extends from long-wavelength radio waves to short-wavelength gamma rays and includes X-rays, microwaves, and infrared (or heat) radiation.

The study of heat, thermodynamics, and statistical mechanics

 

The study of heat, thermodynamics, and statistical mechanics

Heat is a form of internal energy associated with the random motion of the molecular constituents of matter or with radiation. Temperature is an average of a part of the internal energy present in a body (it does not include the energy of molecular binding or of molecular rotation). The lowest possible energy state of a substance is defined as the absolute zero (−273.15 °C, or −459.67 °F) of temperature. An isolated body eventually reaches uniform temperature, a state known as thermal equilibrium, as do two or more bodies placed in contact. The formal study of states of matter at (or near) thermal equilibrium is called thermodynamics; it is capable of analyzing a large variety of thermal systems without considering their detailed microstructures.

First law

The first law of thermodynamics is the energy conservation principle of mechanics (i.e., for all changes in an isolated system, the energy remains constant) generalized to include heat.

Second law

The second law of thermodynamics asserts that heat will not flow from a place of lower temperature to one where it is higher without the intervention of an external device (e.g., a refrigerator). The concept of entropy involves the measurement of the state of disorder of the particles making up a system. For example, if tossing a coin many times results in a random-appearing sequence of heads and tails, the result has a higher entropy than if heads and tails tend to appear in clusters. Another formulation of the second law is that the entropy of an isolated system never decreases with time.

Third law

The third law of thermodynamics states that the entropy at the absolute zero of temperature is zero, corresponding to the most ordered possible state.

Statistical mechanics

 

The science of statistical mechanics derives bulk properties of systems from the mechanical properties of their molecular constituents, assuming molecular chaos and applying the laws of probability. Regarding each possible configuration of the particles as equally likely, the chaotic state (the state of maximum entropy) is so enormously more likely than ordered states that an isolated system will evolve to it, as stated in the second law of thermodynamics. Such reasoning, placed in mathematically precise form, is typical of statistical mechanics, which is capable of deriving the laws of thermodynamics but goes beyond them in describing fluctuations (i.e., temporary departures) from the thermodynamic laws that describe only average behaviour. An example of a fluctuation phenomenon is the random motion of small particles suspended in a fluid, known as Brownian motion.

Quantum statistical mechanics plays a major role in many other modern fields of science, as, for example, in plasma physics (the study of fully ionized gases), in solid-state physics, and in the study of stellar structure. From a microscopic point of view the laws of thermodynamics imply that, whereas the total quantity of energy of any isolated system is constant, what might be called the quality of this energy is degraded as the system moves inexorably, through the operation of the laws of chance, to states of increasing disorder until it finally reaches the state of maximum disorder (maximum entropy), in which all parts of the system are at the same temperature, and none of the state’s energy may be usefully employed. When applied to the universe as a whole, considered as an isolated system, this ultimate chaotic condition has been called the “heat death.”

The study of gravitation

 

The study of gravitation

Laser Interferometer Space Antenna (LISA), a Beyond Einstein Great Observatory, is scheduled for launch in 2034. Funded by the European Space Agency, LISA will consist of three identical spacecraft that will trail the Earth in its orbit by about 50 million km (30 million miles). The spacecraft will contain thrusters for maneuvering them into an equilateral triangle, with sides of approximately 5 million km (3 million miles), such that the triangle's centre will be located along the Earth's orbit. By measuring the transmission of laser signals between the spacecraft (essentially a giant Michelson interferometer in space), scientists hope to detect and accurately measure gravity waves.(more)

This field of inquiry has in the past been placed within classical mechanics for historical reasons, because both fields were brought to a high state of perfection by Newton and also because of its universal character. Newton’s gravitational law states that every material particle in the universe attracts every other one with a force that acts along the line joining them and whose strength is directly proportional to the product of their masses and inversely proportional to the square of their separation. Newton’s detailed accounting for the orbits of the planets and the Moon, as well as for such subtle gravitational effects as the tides and the precession of the equinoxes (a slow cyclical change in direction of Earth’s axis of rotation), through this fundamental force was the first triumph of classical mechanics. No further principles are required to understand the principal aspects of rocketry and space flight (although, of course, a formidable technology is needed to carry them out).

The modern theory of gravitation was formulated by Albert Einstein and is called the general theory of relativity. From the long-known equality of the quantity “mass” in Newton’s second law of motion and that in his gravitational law, Einstein was struck by the fact that acceleration can locally annul a gravitational force (as occurs in the so-called weightlessness of astronauts in an Earth-orbiting spacecraft) and was led thereby to the concept of curved space-time. Completed in 1915, the theory was valued for many years mainly for its mathematical beauty and for correctly predicting a small number of phenomena, such as the gravitational bending of light around a massive object. Only in recent years, however, has it become a vital subject for both theoretical and experimental research. (Relativistic mechanics refers to Einstein’s special theory of relativity, which is not a theory of gravitation.)