Physics Laws of Motion

Internal forces in an isolated system do not affect the total momentum. But do note that the mutual forces between pairs of particles in the system can cause individual particles to change their momentum. Now, these internal forces are always equal and opposite, as you can recall from Newton's Third Law. 
Due to that, the individual momentum changes cancel out in pairs. What happens is that the total momentum of the system remains unchanged. That further allows the Second Law of Motion to be applied to a body or a system of particles. The internal forces sum to a force that is mathematically nulled out. 

An isolated system is one that has no external force acting on it. This means that for the total momentum to remain unchanged, there must be no net force originating from outside the system. This net external force should not be able to influence the motion of the isolated system, as per the law of conservation of momentum.

In the frame of vehicle, vehicle is in equilibrium under the influence of pseudo force F_P

  $F_P=\frac{m{v}^2}{R}$            

N = mg cos 30° + F_P sin 30°

$\Rightarrow N=mgcos30°+\frac{m{v}^2}{R}sin30°.\left(i\right)$              

, and

$f_S=\frac{m{v}^2}{R}cos30°-mgsin30°$              

By doing (1) * cos 30° - (2) * sin 30°, we have

$\Rightarrow N=\frac{800*10}{0.87-0.2*0.5}=\frac{800*10}{0.77}=10.2*10^{3}kgm/s^2$

De Broglie wavelength

$\lambda =\frac{h}{mV}=\frac{h}{\sqrt[]{2mE}}E\to K.E.$              

$E=\frac{3}{2}$  KT for gas

$So\lambda =\frac{h}{\sqrt[]{3mKT}}=\frac{6.6*10^{-34}}{\sqrt[]{3*9*10^{-31}*1.38*10^{-23}*300}}$

$\begin{array}{l}\lambda =6.26*10^{-9}m\\ \lambda =6.26nm\end{array}$                

Aristotle's main flaw was that he did not account for forces already present that keep a body at rest or in motion. In classical antiquity physics, during this philosopher's time, invisible and opposing forces, such as friction and air resistance, were not understood. So, it was natural to resort to observation-based answers that would later get disproved by scientists like Galileo and Newton, who introduced rigorous experimentation and mathematical enquiries.

Yes, all objects have inertia. It does not depend on whether they are moving or not. Inertia is an object's inherent resistance to any change in its state of motion.

For an object at rest, its inertia is its tendency to remain at rest. A force is required to overcome this inertia and set the object in motion. 

The amount of inertia an object has is determined by its mass. The more massive an object is, the more it resists a change in its state of motion. We can also say that this heavier object has greater inertia.

The law of inertia, also known as Newton's first law of motion, states that an object at rest will stay at rest. Likewise, an object in motion will remain in motion with the same speed and in the same direction unless there is a net external force. 

Now in both ideal states, the net external force on an object is zero.

From the perspective of classical mechanics, there isn't a significant distinction between rest and uniform motion. They can be seen as the same state of motion viewed from different reference frames. An object is considered to be in a state of equilibrium whether it is at rest or in uniform motion.