# Newton s first law of

Balanced and Unbalanced Forces In a previous chapter of studythe variety of ways by which motion can be described words, graphs, diagrams, numbers, etc. In this unit Newton's Laws of Motionthe ways in which motion can be explained will be discussed. Also called the law of inertia, this is the most important thing to realize about motion. Why do objects slow down? Before Galileo and Newton, many people thought objects slowed down because they had a natural built in tendency to do so.

But those people weren't taking into account the many forces—e. If we could observe the motion of an object in deep interstellar space, we would be able to observe the natural tendencies of an object's motion free from any external influences.

In deep interstellar space, we would observe that if an object had a velocity, it would continue moving with that velocity until there was some force to cause a change in the motion.

Similarly, if an object were at rest in interstellar space, it would remain at rest until there was a force to cause it to change its motion. In the video below, we can see that objects in the international space station either remain at rest or continue with constant velocity relative to the space station until acted upon by a force.

But since the space station is in free fall orbiting around the Earth, from inside the ISS, it's as if there were no gravitational force at all.

There is air in the ISS—since astronauts have to breathe—and so there would be some air resistance.

## Newton's laws of motion

However, since everything is in free fall, objects don't immediately plummet and make contact with the floor, so the force of friction is much less of a distracting influence on the motion of an object. The idea that objects only change their velocity due to a force is encapsulated in Newton's first law.

An object at rest remains at rest, or if in motion, remains in motion at a constant velocity unless acted on by a net external force. Note the repeated use of the verb remains. We can think of this law as preserving the status quo of motion.

An object sliding across a table or floor slows down due to the net force of friction acting on the object. But on an air hockey table, where air keeps the puck from touching the table, the air hockey puck continues moving with a roughly constant velocity until a force acts on it—like when it bumps into the side of the table.

So, the puck wouldn't make it all the way around the Earth. We can't get rid of the air since that is the only thing keeping the puck lifted off the table—it is called air hockey after all. Unfortunately this means that playing air hockey with people in other countries on a table thousands of miles long doesn't seem possible.

This is probably for the better since even if there were no air resistance or friction, it would take hundreds of hours for your air hockey serve in London, England to get returned by someone in Beijing, China.

What do force, external force, and net force mean?

## Newton's First Law

A force is a push or a pull exerted on one object by another object. An external force is a force originating from outside an object rather than a force internal to an object. For instance, the force of gravity that Earth exerts on the moon is an external force on the moon.May 05,  · Sir Isaac Newton first presented his three laws of motion in the "Principia Mathematica Philosophiae Naturalis" in His first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force.

Sir Isaac Newton; First Law of Motion; Second Law of Motion; Third Law of Motion; Review Newton's Laws; Quiz; Quiz Answers; Hot Wheels Lab; Balloon Racers. A force is a push or a pull that acts upon an object as a results of its interaction with another object.

Forces result from interactions! As discussed in Lesson 2, some forces result from contact interactions (normal, frictional, tensional, and applied forces are examples of contact forces) and. Newton's law of universal gravitation states that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. This is a general physical law derived from empirical observations by what Isaac Newton called inductive reasoning. Sir Isaac Newton's Law of Inertia F = m.a.

• Why do objects slow down?
• Newton's First Law

Mass is caused by the Relationship between Change in Velocity c of the In-Wave and the resultant Change in Location of the Wave-Center / . Rocket Equations: Newton's 3rd Law of Motion "Houston, Tranquility Base here, the Eagle has landed!" - Neil Armstrong, Apollo 11, July 20,

What is Newton's first law? (article) | Khan Academy