- #1
arnab321
- 20
- 0
How does a spacecraft move in space where there is vacuum and nothing to provide normal reaction for the motion?
cjl said:Rockets work by throwing fuel out
It's not just Hollywood. The media is quite ignorant of science in general. Witness the recent reentry of the UARS space craft. It didn't matter which news outlet I watched; they all got the basic physics wrong. There was an implicit (and sometimes explicit) assumption on the part of the newsie that in order for a spacecraft to be orbiting the Earth it must be firing its thrusters constantly. Stop firing the thrusters and the satellite will stop orbiting. Immediately. Some announcers just couldn't understand why NASA couldn't control the reentry better.mender said:Hollywood typically ignores basic physics for the sake of entertainment.
Borek said:Not a fuel - reaction (which in many cases can be classified as combustion) products. Unless you mean something like ion thruster.
Newton's laws of motion are three fundamental principles that describe the behavior of objects in motion. The first law states that an object will remain at rest or in motion at a constant velocity unless acted upon by an external force. The second law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. The third law states that for every action, there is an equal and opposite reaction.
Yes, a rocket or spacecraft can move in space without violating Newton's laws. The force that propels the rocket or spacecraft is provided by the expulsion of gases from the rocket's engine, which follows Newton's third law. Additionally, the rocket's mass decreases as the fuel is consumed, allowing it to accelerate according to Newton's second law.
In terms of Newton's laws, a rocket or spacecraft will behave the same in a vacuum as it does on Earth. However, the absence of air resistance in a vacuum allows the rocket to travel at higher speeds and with greater efficiency.
Newton's third law states that for every action, there is an equal and opposite reaction. In the case of a rocket or spacecraft, the action is the expulsion of gases from the rocket's engine, and the reaction is the force that propels the rocket forward. This is what allows the rocket to move through space.
No, a rocket or spacecraft cannot violate Newton's first law of motion. This law states that an object will remain at rest or in motion at a constant velocity unless acted upon by an external force. The rocket or spacecraft is constantly experiencing external forces, such as gravity and propulsion, which allows it to change its velocity. However, it is not violating the law as these forces are acting upon it.