The orbital motions of planets and comets, as depicted here, are governed by the laws of mechanics. Click on image for full size (8K GIF) Windows to the Universe original artwork by Randy Russell.

Mechanics is the term used to refer to one of the main branches of the science of physics. Mechanics deals with the motion of and the forces that act upon physical objects. What happens when an asteroid slams into a planet? How should we launch a satellite to put it into a specific orbit? These are the sorts of questions that the principles of mechanics can help us answer.

We need precise terminology to describe the way objects move. Kinematics is the sub-field within mechanics that supplies this lingo in the form of concepts like position, velocity, acceleration, and rotation rates. Forces and the motions they produce, as specified by Newton's Laws of Motion, are within the realm of the closely related discipline of kinetics. Sometimes forces balance out, producing no motion, as is the case when buoyancy and gravity are equal and a balloon floats serenely in the sky. Such circumstances are described by the discipline of statics.

The abstract concept of energy also plays an important role in the study of mechanics. We speak of potential energy in situations such as a ball at rest at the top of a hill, and kinetic energy when that ball is rapidly rolling along after descending the hill. Conversion of energy from one form to another is constrained by the Law of Energy Conservation. Energy is a versatile concept that finds applications in situations involving chemical energy or electromagnetic energy, as well as within mechanics.

The mechanics of individual, solid objects are the simplest to understand, but mechanics also deals with the more complex motions of loosely linked collections of particles. Fluid mechanics describes the motions and forces associated with traditional liquids, such as water. It also delves into the behaviors of other "fluids", including gases such as air and the plasma that makes up the atmosphere of the Sun.

Complex behaviors also arise when objects start spinning or moving along curved paths instead of along straight lines. Earth orbits the Sun along a nearly circular path while spinning upon its axis once each day. Rapidly rotating gyroscopes stabilize satellites, while electrons and protons spiral downward along Earth's magnetic field lines to create auroras. Concepts such as torque, angular velocity and momentum, precession, and rotations per minute (rpm) come into play when objects start spinning and turning.

Humans have long employed the Laws of Mechanics in engineered works. We build simple machines, like levers and screws and pulleys, to make our work proceed more smoothly. We study the nature of the "stuff" from which we make objects, using the findings of materials science to decide to use concrete in assembling buildings, steel in manufacturing automobiles, and aluminum and lightweight composites to produce airplanes.

The orbital motions of planets and comets, as depicted here, are governed by the laws of mechanics. Click on image for full size (8K GIF) Windows to the Universe original artwork by Randy Russell.

Mechanics is the term used to refer to one of the main branches of the science of physics. Mechanics deals with the motion of and the forces that act upon physical objects. What happens when an asteroid slams into a planet? How should we launch a satellite to put it into a specific orbit? These are the sorts of questions that the principles of mechanics can help us answer.

We need precise terminology to describe the way objects move. Kinematics is the sub-field within mechanics that supplies this lingo in the form of concepts like position, velocity, acceleration, and rotation rates. Forces and the motions they produce, as specified by Newton's Laws of Motion, are within the realm of the closely related discipline of kinetics. Sometimes forces balance out, producing no motion, as is the case when buoyancy and gravity are equal and a balloon floats serenely in the sky. Such circumstances are described by the discipline of statics.

The abstract concept of energy also plays an important role in the study of mechanics. We speak of potential energy in situations such as a ball at rest at the top of a hill, and kinetic energy when that ball is rapidly rolling along after descending the hill. Conversion of energy from one form to another is constrained by the Law of Energy Conservation. Energy is a versatile concept that finds applications in situations involving chemical energy or electromagnetic energy, as well as within mechanics.

The mechanics of individual, solid objects are the simplest to understand, but mechanics also deals with the more complex motions of loosely linked collections of particles. Fluid mechanics describes the motions and forces associated with traditional liquids, such as water. It also delves into the behaviors of other "fluids", including gases such as air and the plasma that makes up the atmosphere of the Sun.

Complex behaviors also arise when objects start spinning or moving along curved paths instead of along straight lines. Earth orbits the Sun along a nearly circular path while spinning upon its axis once each day. Rapidly rotating gyroscopes stabilize satellites, while electrons and protons spiral downward along Earth's magnetic field lines to create auroras. Concepts such as torque, angular velocity and momentum, precession, and rotations per minute (rpm) come into play when objects start spinning and turning.

Humans have long employed the Laws of Mechanics in engineered works. We build simple machines, like levers and screws and pulleys, to make our work proceed more smoothly. We study the nature of the "stuff" from which we make objects, using the findings of materials science to decide to use concrete in assembling buildings, steel in manufacturing automobiles, and aluminum and lightweight composites to produce airplanes.

The orbital motions of planets and comets, as depicted here, are governed by the laws of mechanics. Click on image for full size (8K GIF) Windows to the Universe original artwork by Randy Russell.

Mechanics is one of the main branches of physics. Mechanics deals with the motion of physical objects. It also deals with the forces that act on physical objects. How hard do I have to pull a full wagon before it will budge? What happens when an asteroid slams into a planet? How should we launch a satellite to put it into orbit? These are the sorts of questions that the study of mechanics can help us answer.

You may have studied mechanics without knowing it. Have you ever studied or built a simple machine like a lever or pulley? Those machines that make our work easier use the laws of mechanics to work.