What Is Gravity

A ball drops to the ground. Leaves fall from a tree. Gravity is at work all around you. But what exactly is gravity? And how does it affect different objects? Read this book to find out! Learn all about matter, energy, and forces in the Exploring Physical Science series—part of the Lightning Bolt BooksTM collection. With high-energy designs, exciting photos, and fun text, Lightning Bolt BooksTM bring nonfiction topics to life!

Gravity interpretation involves inversion of data into models, but it is more. Gravity interpretation is used in a “holistic” sense going beyond “inversion”. Inversion is like optimization within certain a priori assumptions, i.e., all anticipated models lie in a limited domain of the a priori errors. No source should exist outside the anticipated model volume, but that is never literally true. Interpretation goes beyond by taking “outside” possibilities into account in the widest sense. Any neglected possibility carries the danger of seriously affecting the interpretation. Gravity interpretation pertains to wider questions such as the shape of the Earth, the nature of the continental and oceanic crust, isostasy, forces and stresses, geol- ical structure, nding useful resources, climate change, etc. Interpretation is often used synonymously with modelling and inversion of observations toward models. Interpretation places the inversion results into the wider geological or economic context and into the framework of science and humanity. Models play a central role in science. They are images of phenomena of the physical world, for example, scale images or metaphors, enabling the human mind to describe observations and re- tionships by abstract mathematical means. Models served orientation and survival in a complex, partly invisible physical and social environment.

A simple introduction to gravity, describing what it is and giving some effects of this force.

This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1934.

“Newton’s Gravity” conveys the power of simple mathematics to tell the fundamental truth about nature. Many people, for example, know the tides are caused by the pull of the Moon and to a lesser extent the Sun. But very few can explain exactly how and why that happens. Fewer still can calculate the actual pulls of the Moon and Sun on the oceans. This book shows in clear detail how to do this with simple tools. It uniquely crosses disciplines – history, astronomy, physics and mathematics – and takes pains to explain things frequently passed over or taken for granted in other books. Using a problem-based approach, “Newton’s Gravity” explores the surprisingly basic mathematics behind gravity, the most fundamental force that governs the movements of satellites, planets, and the stars. Author Douglas W. MacDougal uses actual problems from the history of astronomy, as well as original examples, to deepen understanding of how discoveries were made and what they mean. “Newton’s Gravity” concentrates strongly on the development of the science of orbital motion, beginning with Galileo, Kepler, and Newton, each of whom is prominently represented. Quotes and problems from Galileo’s Dialogs Concerning Two New Sciences and particularly Newton’s Principia help the reader get inside the mind of those thinkers and see the problems as they saw them, and experience their concise and typically eloquent writing. This book enables students and curious minds to explore the mysteries of celestial motion without having to know advanced mathematics. It will whet the reader’s curiosity to explore further and provide him or her the tools (mathematical or physical) to do so.

"Of the four fundamental forces of nature, gravity might be the least understood and yet the one with which we are most intimate. From the months each of us spent suspended in the womb anticipating birth to the moments when we wait for sleep to transport us to other realities, we are always aware of gravity. In On Gravity, physicist A. Zee combines profound depth with incisive accessibility to take us on an original and compelling tour of Einstein's general theory of relativity. Inspired by Einstein's audacious suggestion that spacetime could ripple, Zee begins with the stunning discovery of gravity waves. He goes on to explain how gravity can be understood in comparison to other classical field theories, presents the idea of curved spacetime and the action principle, and explores cutting-edge topics, including black holes and Hawking radiation. Zee travels as far as the theory reaches, leaving us with tantalizing hints of the utterly unknown, from the intransigence of quantum gravity to the mysteries of dark matter and energy. Concise and precise, and infused with Zee's signature warmth and freshness of style, On Gravity opens a unique pathway to comprehending relativity and gaining deep insight into gravity, spacetime, and the workings of the universe"--Publisher's website.

APlusPhysics: Your Guide to Regents Physics Essentials is a clear and concise roadmap to the entire New York State Regents Physics curriculum, preparing students for success in their high school physics class as well as review for high marks on the Regents Physics Exam. Topics covered include pre-requisite math and trigonometry; kinematics; forces; Newton's Laws of Motion, circular motion and gravity; impulse and momentum; work, energy, and power; electrostatics; electric circuits; magnetism; waves; optics; and modern physics. Featuring more than five hundred questions from past Regents exams with worked out solutions and detailed illustrations, this book is integrated with the APlusPhysics.com website, which includes online question and answer forums, videos, animations, and supplemental problems to help you master Regents Physics essentials. "The best physics books are the ones kids will actually read." Advance Praise for APlusPhysics Regents Physics Essentials: "Very well written... simple, clear engaging and accessible. You hit a grand slam with this review book." -- Anthony, NY Regents Physics Teacher. "Does a great job giving students what they need to know. The value provided is amazing." -- Tom, NY Regents Physics Teacher. "This was tremendous preparation for my physics test. I love the detailed problem solutions." -- Jenny, NY Regents Physics Student. "Regents Physics Essentials has all the information you could ever need and is much easier to understand than many other textbooks... it is an excellent review tool and is truly written for students." -- Cat, NY Regents Physics Student

How can something that grounds us and keeps us here on this earth be so invisible and mysterious? We’re not talking about anything abstract and undetectable. We’re talking about GRAVITY! Gravity is a force that affects everyone and everything. Gravity is something we can easily understand, even kids, especially if they have the right tools to teach them. Explore Gravity! With 25 Great Projects will introduce kids ages 6-9 to the basics of gravity, including concepts of matter, attraction, and gravitational pull. Projects include creating a working model of a scale to learn what “weight” really means and how it’s affected by gravity. By playing with various weights to make a marvelous mobile, readers learn about the center of balance and how martial artists use this knowledge to throw their weight around. All the projects in this book are easy to follow, require little adult supervision, and use commonly found household products, many from the recycling box! The fun facts, trivia, jokes, comics, and hands-on activities will help kids discover the captivating science of gravity. Furthermore, the informational text and hands-on activities will excite kids about STEM, the interrelated fields of science, technology, engineering, and math.