Do Newton's laws of motion have restrictions
1.3.3 Newton's Laws (modern formulation)After we have defined kinematic quantities for the movement of a mass point and scaled them using a suitable system of measurements, we can now formulate Newton's laws
- A body is at rest or moves at a constant speed when there is no force acting on it
- The change in momentum over time (the momentum is ) of a body is equal to the force acting on the body
- Two bodies exert the same amount of forces on each other, but oppositely directed forces (actio equals reaction). Is called with the force from mass 2 to mass 1 and with the opposite situation applies
These three laws are sufficient to understand classical mechanics: they describe motion processes on earth, in the solar system or the dynamics of galaxies. However, we will formulate restrictive conditions later. Put simply, the restrictions are: Newton's laws apply to systems that move much slower than light in a vacuum and are macroscopic.
- Newton's synthesis consists in the abstraction that the laws for the movement of bodies on earth are the same as in space.
- The first law says that constant speed movement is the natural state of a force-free body. Since we cannot in principle define an absolute reference system, the first law allows us to choose any system that moves with constant speed - inertial system: every inertial system is equivalent to the description of physical processes (principle of relativity).
- From the second law it follows for masses that are constant in time There usually from and we have an equation of motion for a classical systemThis is an ordinary 2nd order differential equation for determining location and impulse of a system. We need to know the forces at work and the initial state of the system , everything else is clearly determined by the equation of motion.
- A consequence of the third law is the conservation of momentum in a closed system of mass points. This is understood to mean a system on which no external forces act. For two mass points, the sum of their momentum applies The corresponding extension for N mass points is analogousThe total momentum of a system of mass points is the same at all times and is therefore a conservation quantity if only internal forces between the mass points and no external forces act on the system.
- So what is a force? Mechanics don't give us an answer to that.
How do we experience a force? E.g. in the form of Newton's law of gravitation (details later)It applies to the falling apple (M: mass of the earth, m: mass of the apple) as well as to the movement of the planets (M: mass of the sun, m: e.g. mass of the earth).
What does the force do? According to the second law, it causes a change in momentum and thus an accelerated movement
U. Lechner, H.J. Ludde
- When is intelligent considered disadvantageous
- How many online stores do we have
- Which vitamins help with tiredness
- Are ceramic utensils always microwave safe?
- What happened to Italian football?
- Can Joker be arrested in real life
- How does WIPRO motivate its employees
- What does the UAE look like
- New York is on a peninsula
- Should I keep learning web design
- Is honey good for arthritis?
- Which is the best online WordPress training institute
- Hillary Clinton speaks to the dead
- How does FinFET reduce leakage current
- Can solar energy be nice
- When should a teenager start shaving?
- How many miles can a car last
- What is the fateful encounter hypothesis
- How do people deal with cyberbullying
- Julian Assange is a Harvard alumnus
- When is contemporary art no longer appropriate?
- Did your wanderlust lead you to love
- Japan and South Korea are military allies
- Why do people choose to follow questions