Suppose that you are standing on a cardboard carton that just barely supports you.What would happen to it if you jumped up into the air?

It would spring upward a bit.
It would move sideways.
It would be unaffected.
It would collapse.

It would collapse, because you have to exert a downward force to go up. By pushing down on the cardboard that barely holds you, it will probably collapse.

If you jump up into the air while standing on a cardboard carton that just barely supports you, the most likely outcome is that the carton would collapse. This is because the force exerted on the carton when you jump up creates an upward force that exceeds the carton's maximum load-bearing capacity. Since the carton is not strong enough to withstand this force, it would buckle and collapse under your weight. To determine the outcome with certainty, you could perform a simple experiment where you place the carton on a scale and measure the maximum amount of weight it can support without collapsing. By comparing this measurement to your own weight, you can determine whether the carton will collapse when you jump on it or not.