Chitchat Nah. Rocket cannot fly in vaccum space. AMJS con u again

[tanwahtiu]

Rocket cannot fly in space. Angmoh jiak sia cheat u more...

 

[virus]

eh.. that's a snake making explanation, you trust a snake?

 

[Leongsam]

eh.. that's a snake making explanation, you trust a snake?

Nothing to do with with snakes he's a moron. Rockets don't move forward because they're pushing against something.

http://www.explainthatstuff.com/spacerockets.html

Rockets are great examples of how forces make things move. It's a common mistake to think that rockets move forward by "pushing back against the air"—and it's easy to see that this is a mistake when you remember that there's no air in space to push against. Space is literally that: empty space!

When it comes to forces, rockets perfectly demonstrate three important scientific rules called the laws of motion, which were developed about 300 years ago by English scientist Isaac Newton (1642–1727).

1. A space rocket obviously doesn't go anywhere unless you start its engine. As Newton said, still things (like rockets parked on launch pads) stay still unless forces act on them (and moving things keep moving at a steady speed unless a force acts to stop them).
2. Newton said that when a force acts on something, it makes it accelerate (go faster, change direction, or both). So when you fire up your rocket engine, that makes the force that accelerates the rocket into the sky.
3. Rockets move upward by firing hot exhaust gas downward, rather like jet planes—or blown-up balloons from which you let the (cold) air escape. This is an example of what's often called "action and reaction" (another name for Newton's third law of motion): the hot exhaust gas firing down (the action) creates an equal and opposite force (the reaction) that speeds the rocket up. The action is the force of the gas, the reaction's the force acting on the rocket—and the two forces are of equal size, but pointing in opposite directions, and acting on different things (which is why they don't cancel out).

 

[Leongsam]

A rocket consists essentially of an engine plus fuel - it is the job of the engine to burn the fuel and throw the products out of the end of the rocket. The operation of a rocket is an excellent example of the Law of Conservation of Momentum, as shown below:



Before the Engine Fires:
Let's take our system as "rocket + fuel". For simplicity, suppose that the rocket is at rest, somewhere in space, where no outside forces will exert impulses on our system. Therefore, "rocket plus fuel" is an isolated system and the Law of Conservation of Momentum applies. Since both the rocket and the fuel are at rest, their individual momenta are zero, and so the total momentum of the system is zero.

After the Engine Fires:
When the rocket's engine fires, it pushes fuel out of the end of the rocket. Suddenly, part of the fuel has momentum, mv, toward the left as shown in the diagram.

Since the total momentum of the system was zero before the rocket fired, it must still be zero. This means that the rocket must have an equal momentum to the right:

procket = -pfuel
The negative sign means that the two momentum vectors are in opposite directions (and therefore cancel). Even though the momentum of the rocket and the momentum of the fuel are the same size, their velocities are not the same size. Since the fuel has a small mass, it gets a larger velocity. Since the rocket has a large mass, it gets a smaller velocity.

Mrocketvrocket = -mfuelVfuel

 

[pakchewcheng]

A rocket consists essentially of an engine plus fuel - it is the job of the engine to burn the fuel and throw the products out of the end of the rocket. The operation of a rocket is an excellent example of the Law of Conservation of Momentum, as shown below:



Before the Engine Fires:
Let's take our system as "rocket + fuel". For simplicity, suppose that the rocket is at rest, somewhere in space, where no outside forces will exert impulses on our system. Therefore, "rocket plus fuel" is an isolated system and the Law of Conservation of Momentum applies. Since both the rocket and the fuel are at rest, their individual momenta are zero, and so the total momentum of the system is zero.

After the Engine Fires:
When the rocket's engine fires, it pushes fuel out of the end of the rocket. Suddenly, part of the fuel has momentum, mv, toward the left as shown in the diagram.

Since the total momentum of the system was zero before the rocket fired, it must still be zero. This means that the rocket must have an equal momentum to the right:

procket = -pfuel
The negative sign means that the two momentum vectors are in opposite directions (and therefore cancel). Even though the momentum of the rocket and the momentum of the fuel are the same size, their velocities are not the same size. Since the fuel has a small mass, it gets a larger velocity. Since the rocket has a large mass, it gets a smaller velocity.

Mrocketvrocket = -mfuelVfuel

Fuck!

You so wuliao that you need to explain this as your contribution of pearls to the great unwashed?

 

[tanwahtiu]

Newton is angmoh and AMDK he loved his arse poked.