Why does a satellite move without needing a force to push it?

Question

Why does a satellite move without needing a force to push it?

Answer 1

Satellites are in the environment where there is no gravity so they freely move in 0 gravitational force

Answer 2

Satellites definitely do need a force to push them. It's called a rocket. The satellite must be accelerated to over 17000 miles per hour just so they'll stay up in space. Of course, in space, there's almost no friction to slow them back down, so they're essentially coasting around and around the world.

There is still a tiny bit of very thin atmosphere up there, which over time gradually slows them back down. This is why satellites have on-board thrusters - they use them periodically to boost back up and overcome the lost speed due to friction with the atmosphere.

Remember all the hoopla over the spy satellite that was crashing? The concern was over its toxic rocket fuel. This is the fuel that was supposed to keep the satellite up in orbit, but since the satellite failed on launch, it had never used any of its fuel, so the worry was that a full tank of hydrazene might survive reentry and potentially land somewhere that it would poison the environment.

As others have said, satellites are constantly pulled by the force of gravity, which is what keeps them moving in a circle around the Earth in stead of straight out into space.

Your car needs constant force from its engine because of all of the friction from the air, and in the axles and other mechanical parts that keep it moving.

Answer 3

Well, upon launch, all the force it needed was added to it.  Once in orbit, there's very little friction to slow it down, so it continues in it's motion.  As long as no external force acts on it, there will be no change in direction or velocity.  

Answer 4

it does have a "force" contributing to its moving.

Satellites are on a "free" fall.

Also, gravity allows for this to happen.

Answer 5

Because when it was launched, it was pushed with great force, and since that time there has been almost nothing to slow it down. It is still falling around the Earth at very high speed, and will continue doing so until the very slight resistance to its motion slows it down enough that it can fall into the atmosphere and burn up.

Answer 6

earth's gravity force pulls on the satellites making them stay in orbit

Answer 7

It DID, at one time, have a force pushing it. that force came from the rocket that launched it.

According to Newton's First Law, "A body in motion tends to sty in motion unless operated on by an outside force". most cases that "outside force" is friction. Notice how cars operate on concrete, and on the same copncrete covered with ice!

In space, there is only one "outside force" to operate on an object - gravity. Gravity keeps pulling the the satellite DOWN, but it "misses" the earth! In effect, the satellitel is falling but the earth moves out of the way.

But as the satellitel moves closer and closer to earth there is just a little friction from the very thin atmosphere that is still left. This friction casues the satelitel to slow down every so slightly, which results in just a slightly lower orbit (measured in fractions of an inch . . .)

Eventually, the speed of the satellite 'deteorates" to the point that it can no logner overcomes the force of gravity,. adn the satellite will re-enter the earth's atmosphere and butn up.

these are attracted by the gravitational force keeping them in orbit.

sensors the eye in satellites catch photos and send it to the space stations.these act as an eye in sky.

Answer 8

Actually, its always falling, but the centrifugal force is pushing it up at the same time, keeping it in orbit. Think of a merry-go-round.

Answer 9

Satellites are sent into space using rocket.When a rocket is launched  its escape velocity overcomes the gravitational force of the earth and the satellite is launched in space.Once its out of the earth,there is very little friction there and hence the satellite will move in the required orbit and will continue to do so until we apply some external force on it.

Answer 10

the satillite will be given force firstly atlaunching

by newton3 law it moves due o the opposite force and

while in space due to gravitational force it moves

r we can say that centrifugal forces applied by the earth and sun on satellite makes it move

Answer 11

Satellites move by the gravity force keeping them in a elliptical or circular trajectory around the planet. They just need a strong enough initial push, to be so fast that, while gravity pulls them to the planet, they miss the planet all the time.

Answer 12

Newton's first law of motion, which says an object in uniform motion will stay moving in that same motion forever unless acted on by a force to stop it. Newton was a genius for figuring that out in spite of the fact that the opposite seems to be the case. The force of friction is always present on Earth and in the air to stop motions. But in the vacuum of space there is no air and no friction, so a moving satellite (or planet) can just coast on in its orbit forever. How smart did Newton have to be to figure that out hundreds of years before space travel was possible?

Answer 13

There are actually two forces causing satellites to move. One force is the satellite's initial velocity through space, provided by its launch engine(s). The other force is Earth's gravity trying to pull the satellite down. The two forces cancel and the satellite ends up moving around Earth.

Answer 14

Quite a lot of force is need to "push" a satellite into orbit actually, That is why big expensive rockets are used.

Answer 15

actually it moves due to centripetal force but doesnt go off tangentially due to the gravitational force, also it does not fall on earth due to the same centripetal force

Answer 16

because it is in the the orbit.due to gravitational force &magnetic field of that planet in which the satellite is moving.

Answer 17

When a satellite is in orbit, its forward motion is balanced by its downward motion. The initial force that moves a satellite is the rocket used to lift it off the ground. This gives the satellite the kinetic energy that is its forward momentum and keeps it moving. Since there is no friction in space, it never loses that momentum. But since Earth is constantly pulling the satellite 'down,' the satellite always stays close to Earth, rather than flying away from Earth completely. These two forces balance each other and create a circular orbit.

Answer 18

It DID, at one time, have a force pushing it.  that force came from the rocket that launched it.

According to Newton's First Law, "A body in motion tends to sty in motion unless operated on by an outside force". most cases that "outside force" is friction.  Notice how cars operate on concrete, and on the same copncrete covered with ice!

In space, there is only one "outside force" to operate on an object - gravity.  Gravity keeps pulling the the satellite DOWN, but it "misses" the earth!  In effect, the satellitel is falling but the earth moves out of the way.

But as the satellitel moves closer and closer to earth there is just a little  friction from the very thin atmosphere that is still left.  This friction casues the satelitel to slow down every so slightly, which results in just a slightly lower orbit (measured in fractions of an inch . . .)

Eventually, the speed of the satellite 'deteorates" to the point that it can no logner overcomes the force of gravity,. adn the satellite will re-enter the earth's atmosphere and butn up.