Does normal force affect other bodies in contact with the body to which the normal is applied? Imagine a big box (2) sitting on the ground and another smaller box (1) resting on (2).
The ground applies a normal force (N2) on (2), taking in account the mass of both (1) and (2). A normal force (N1) is applied on (1). If (N2) "pulls" up (2), does (2) pull up (1) with an equal force to (N2)? If that's the case, when calculating (N1), should we take in account (N2) when using Newton's 2nd law?
See the picture and comment whether the correct option is Option 1 or Option 2 (when looking at body 1's Y axis).
Thank you in advance.
 A: I am not going to directly answer your question(this site has a Homework-like-questions policy) but I would like to correct some misconceptions or provide a more rigorous approach so that you can solve it yourself. 
Notice that the the normal reaction force is a reaction force, that is, it depends on the resultant downward force applied by an object on a surface and the surface hence applies an equal force upwards on the object(These are a Newton’s Third Law Pair as these forces are essentially from repulsion of electron clouds in the atoms of one object and the other). 
Start from interpreting the free body diagram of the top block(Block 1). It has a Weight $W_1$ so the box is pushing down on Block 2 with a contact force equal to $W_1$, so this is the normal force, $N_1$ on Block 2 from Block 1 and now Block 2 thus pushes back on Block 1 with an equal and opposite force of $N_1$ on Block 1. Thus Block 1 is at equilibrium as it’s own weight is now balanced by a normal reaction force($N_1$) from Block 2.
Now notice the forces on Block 2. Remember that it was pushed downwards by $N_1$ from Block 1. Now Block 2 has two forces acting downward on it, the force $N_1$ and its own weight, $W_2$ so it pushes the ground by a normal force equal to this resultant downward force which is ($W_2 + N_1$), so the ground pushes Block 2 by a force equal to ($W_2 + N_1$). Which is the normal reaction force $N_2$. Notice that $N_1=W_1$ so $$N_2=W_1+W_2$$ 
Hence it seems like the normal reaction force of the ground is due to the weight of the combined objects but the actual origin is due to the normal reaction forces involved in-between the boxes, resulting into the final observation. 
