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.