Space Travel: How Do Spaceships Move?

In summary, a spaceship moves in space according to Newton's first law and the law of conservation of linear momentum. It propels itself by ejecting mass in the opposite direction and uses friction to reduce its speed. Friction is not the force that propels a spaceship, it is only a hindrance. The same concept can be observed with a ball and skates on ice, or with a gun or roller skates. The movement is caused by the conservation of linear momentum, not by friction. Additionally, objects can be moved without friction, such as with a speaker using magnetism.
  • #1
Tido611
79
0
OK to my knowledge everything moves by using friction,or pushing off of something but how would say a spaceship move, i know that I am over looking somthing very obvious but I am just not sure what it is.
 
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  • #2
In space, a spaceship moves according to Newton's first law (if it is at constant speed, it will continue to do so eternally, since no force is acting on it [don't nitpick!]), and it changes its direction or accelerate by making use of the law of conservation of linear momentum: it will propulse stuff in the direction opposite from where he wants to go.
 
  • #3
For example, the reason a spaceship would fly is basically its firing mass out of its exhaust and according to Newton's "Equal and opposite reaction" (forget the #... god I am horrible), an equal amount of momentum will be applied in the opposite direction thus propelling the rocket through space. Fricton has nothing to do with movement other then the fact that if there is friction, its speed will be reduced.
 
  • #4
ok i already understood what you guys are saying but i can't wrap my mind around the fact that it has nuttin to push off of or anyhitng like that, that is what i ment when i was mentioning friction.
 
  • #5
Tido611 said:
ok i already understood what you guys are saying but i can't wrap my mind around the fact that it has nuttin to push off of or anyhitng like that, that is what i ment when i was mentioning friction.

Hold a ball while standing on skates on ice. Now throw the ball in one direction. You will see that you will move in the opposite direction. This is conservation of linear momentum. The volume of gasses escaping from jet engines and rocket nozzles do just that.

Zz.
 
  • #6
ZapperZ said:
Hold a ball while standing on skates on ice. Now throw the ball in one direction. You will see that you will move in the opposite direction. This is conservation of linear momentum. The volume of gasses escaping from jet engines and rocket nozzles do just that.

Zz.

Or shoot a gun. much funner and safer!
 
  • #7
Tido611 said:
ok i already understood what you guys are saying but i can't wrap my mind around the fact that it has nuttin to push off of or anyhitng like that, that is what i ment when i was mentioning friction.

Friction isn't "being pushed off of" something. Friction... well it gets in the way of things.
 
  • #8
ZapperZ said:
Hold a ball while standing on skates on ice. Now throw the ball in one direction. You will see that you will move in the opposite direction. This is conservation of linear momentum. The volume of gasses escaping from jet engines and rocket nozzles do just that.

Zz.
Or have you and your friend on roller skates, and push off him/her. You will find that you both move in opposite directions. It will not make much difference how far you travel if you coat your hands in vaseline or with sandpaper gloves.

You've probably seen speakers, when turned up loud enough, that the membrane moves back and forth considerably. On the inside, there is no friction going on to move that. It is moved by magnetism.
 

1. How do spaceships move in outer space?

In order for a spaceship to move in outer space, it must use a propulsion system. This can include rockets, ion thrusters, or solar sails. These systems generate thrust, which propels the spaceship forward.

2. What is the difference between fuel and propellant?

Fuel is a substance that is burned to produce energy, while propellant is the substance that is ejected from a spacecraft to create thrust. In most cases, fuel is used to power the propellant, which then creates the thrust needed for space travel.

3. How do rockets work?

Rockets work by following Newton's Third Law of Motion, which states that for every action, there is an equal and opposite reaction. In a rocket, fuel is ignited and expelled out of the back of the rocket, creating a force in the opposite direction and propelling the rocket forward.

4. Can spaceships move without fuel?

No, spaceships cannot move without some form of propellant. Even if a spaceship is using solar sails, it still needs some form of energy to power the sails and propel the spacecraft forward.

5. How fast can spaceships travel?

The speed of a spaceship depends on the type of propulsion system it is using and the distance it is traveling. For example, rockets can reach speeds of up to 25,000 miles per hour, while ion thrusters can reach speeds of over 100,000 miles per hour. However, due to the vast distances in space, it can still take years for a spaceship to reach its destination.

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