I do not like Yes/No answers so explanations are necessary.
Explanations added are fine, as long as you also give the yes/no answer. Which you have done, so thank you.
Yes - a falling object always apply a force F1 equal to its weight (mg) on whatever it falls onto and whatever it falls on applies a force -FI on the falling object. No more, no less. F1 is constant. Answer is Yes to question 1.
Ah, but "F1" is not the total force that a falling object applies to whatever it falls on, which is what I was asking about. F1 is the component of that total force that is the object's weight.
As this contact + what happens later is a dynamic event, whatever it falls onto also applies a damping force F2 (a new force function of many parameters independent of, e.g. m) on the falling object and the falling object evidently applies an equal force -F2 on the whatever it falls on. F2 is variable in time.
That part is correct...
F2 normally arrests, e.g. any destruction caused by the contact.
... and that part is wrong, for any reasonable definition of "normally." When a large tree falls on a car, for instance, nothing arrests the destruction of the car. The car is destroyed.
So it is not the falling object that applies F2 on whatever it falls on, but the contrary. The falling object can only apply F1 on whatever it falls on.
That contradicts what you just said in the previous paragraph.
"The falling object evidently applies an equal force -F2 on the whatever it falls on."
"The falling object can only apply F1 on whatever it falls on."
The first is basically correct, the second is not. You have in fact just shown that the falling object applies F1 + F2 on the object it falls on. Simple.
(Please don't try to confuse the issue with the minus sign you put on F2. That sign in that context means only that the force is in the opposite direction as the F2 applied to the falling object by the object it's falling on. Force -F2 applied dynamically by the falling object to the object it falls on is in the same direction as F1, the weight of the object, so the magnitude of the total force on the object fallen on is correctly F1 + F2.)
So answers to questions 2 and 3 are No, No.
No, those answers are wrong.
The answer to question 3 is clearly yes, because as you have just shown, the falling object applies F1 + F2. Since F1 is the weight, F1 + F2 is more than the weight.
The answer to question 3 is also yes, for instance in certain cases where the object being fallen on is itself already moving.
In summary, it appears that through the discussion in these threads (this pizza box experiment thread and the scale experiment thread) you are becoming aware of the nature of dynamic forces whose existence you have previously denied or at least ignored.
So, recognizing that dynamic forces occur in collisions (including collisions resulting from falls), and that the dynamic forces are distinct from the weight of the falling object and can be significantly larger in magnitude, let's return to the pizza box experiment.
The pizza box experiment (if you ever actually performed it and if it had the outcome you predict) demonstrates that a structure, dropped onto another structure that is capable of supporting three times the dropped structure's static weight,
from a distance of about 3.7 centimeters, does not destroy the lower structure.
The World Trade center tower collapses demonstrate that a structure, dropped onto another structure that is capable of supporting three times the dropped structure's static weight,
from a distance of 370 centimeters, does destroy the lower structure.
Where is there any contradiction between these results? Wouldn't you expect a fall from a hundred times greater distance to have a greater effect?
What happens in your pizza box thought experiment if you space your pizza boxes 370 centimeters apart, and drop the falling ones from a relative height of 370 centimeters?
Respectfully,
Myriad
