Physical mechanics combines physics, the study of matter in our universe, and investigating how force affects motion, in this case, mechanical structures or machines. While mechanics are generally looked at as a branch of engineering, physics must be considered to create advanced mechanics like rockets. A machine with spacecraft propulsion can be electric or chemical, meaning that physical mechanics and engineering are fundamental for space exploration.
A machine can be defined as a physical system that relies on power and force to propel it to function. Newton’s laws of motion, the main concepts in the study of physics, look at how changes in the motion of an object affect force and mass. Specifically, Newton’s three laws of motion state that every action has an equal and opposite reaction, as seen in rockets and machines. By looking at spacecraft engines’ jet propulsion, we can see this law in action: the rocket moves forward, and the gas pushed out the back of the rocket moves backward, which is the opposite reaction. This gas produces the opposite reaction with fuel carried in the spacecraft, combined with oxygen, inside a chamber, where it is set on fire. When this fuel burns, it fires out the back of the rocket, thrusting it forward, a process that shows Newton’s laws called Jet propulsion; with this, the spacecraft pushes on the fuel it exhausts, and inversely, the fuel pushes the rocket forward.
Similarly, the first physicist and astronomer to use a telescope, Galileo, figured out that things in motion don’t need to have continued force to move but can continue without net force. If this sounds familiar, it is the principle of inertia that allows rockets to continue driving without additional force unless they are inherently stopped. Considering their physical properties, I will explain how rockets work, starting with the launch. The spacecraft must be able to move past Earth’s atmosphere, which is done by an eruption of the fuel and oxidant. This exhaust is pushed out the back of the rocket, creating the action that is opposed by the force that pushes the rocket forward. After this, the rocket must accelerate at a high speed, so mechanical engineers designed the spacecraft to be steered by the control of the nozzle that pushes out the fuel. This changes the direction of the rocket’s force. The engines that use Newton’s 3rd law work alongside rocket motors which are used to boost the rocket and provide extra energy. This is done by firing fuel, especially for rockets that need more energy to get out of Earth’s atmosphere. Overall, the physical mechanics seen in the design and outcomes of spacecraft technology are highlighted in principles of physics and engineering and are fundamental to comprehending how these rockets function, with factors of motion and propulsion.
Sources:
- https://theconversation.com/curious-kids-how-exactly-does-a-spaceship-get-into-space-172402
- https://www.northropgrumman.com/space/spacecraft-design-the-art-and-science-of-breaking-barriers
- https://science.nasa.gov/learn/basics-of-space-flight/chapter3-4/
- https://www.nasa.gov/learning-resources/for-kids-and-students/what-is-a-rocket-grades-k-4/
In Orbit 