Solar System and Gravity
The Effects of Gravity
There are some people who worry that when they 're outside, if they don 't keep a
good grip on the ground, they 'll just go flinging off into space. They needn 't really worry
about this, because gravity generally keeps that sort of thing from happening. The thing is,
no one is really sure what causes gravity, but the effects have been studied by many
physicists and astronomers. Three of the more obvious effects of gravity are things falling
down, weight, and the the moon and planets staying in their orbits.
Things fall down. People have generally grown to accept that if one lets go of
one 's prized and valuable textbook when walking through a mud puddle, the book will
invariably end up in the puddle and therefore be stripped of all value and even legibility.
Things fall down because there is a strong gravitational attraction between things of great
mass, like the Earth, and things of little mass, like a book. The only problem with this
relatively simple explanation is that no one really knows why it 's like that. What people
have figured out so far is that gravity is a force, and a force is anything that changes the
state of rest or motion of an object. In the absence of outside forces, the momentum of a
system remains constant. This means that if there was no gravity, when one would
relinquish one 's hold on the textbook, it would remain at rest in the air. If a force acts on a
body, the body accelerates in the direction of the force. In the example of the force of
gravity, small things like textbooks are pulled downward toward the center of the large
mass of the Earth, not up into space, even if some people think that this might happen. Torgerson 2
Isaac Newton was the first to conceive of weight as the gravitational attraction
between a body and the Earth. The force that results from the gravitational attraction of
the Earth on bodies at its
There are some people who worry that when they 're outside, if they don 't keep a
good grip on the ground, they 'll just go flinging off into space. They needn 't really worry
about this, because gravity generally keeps that sort of thing from happening. The thing is,
no one is really sure what causes gravity, but the effects have been studied by many
physicists and astronomers. Three of the more obvious effects of gravity are things falling
down, weight, and the the moon and planets staying in their orbits.
Things fall down. People have generally grown to accept that if one lets go of
one 's prized and valuable textbook when walking through a mud puddle, the book will
invariably end up in the puddle and therefore be stripped of all value and even legibility.
Things fall down because there is a strong gravitational attraction between things of great
mass, like the Earth, and things of little mass, like a book. The only problem with this
relatively simple explanation is that no one really knows why it 's like that. What people
have figured out so far is that gravity is a force, and a force is anything that changes the
state of rest or motion of an object. In the absence of outside forces, the momentum of a
system remains constant. This means that if there was no gravity, when one would
relinquish one 's hold on the textbook, it would remain at rest in the air. If a force acts on a
body, the body accelerates in the direction of the force. In the example of the force of
gravity, small things like textbooks are pulled downward toward the center of the large
mass of the Earth, not up into space, even if some people think that this might happen. Torgerson 2
Isaac Newton was the first to conceive of weight as the gravitational attraction
between a body and the Earth. The force that results from the gravitational attraction of
the Earth on bodies at its
Cited: Goldsmith, Donald. The Astronomers. New York: St. Martin 's Press, 1991 Newman, James R. The Harper Encyclopedia Of Science. 2nd ed. New York: Harper and Row, 1967. Macmillan. The New York Public Library Science Desk Reference. New York: The Stonesong Press Inc. and The New York Public Library, 1995. .