ELi5: Decades ago when countries were still testing nuclear bombs sometimes the scientists incorrectly predicted how large the explosions would be. How did they accurately calculate the actual size of the explosions after the fact?

Question

As the title says

In: 6

Answer 1

They looked at the results.

We know that if we detonate a tonne of tnt we will get an explosion of a certain size – sit it on the ground and it will make a certain size of crater, and the blast wave will be of a certain pressure at a set distance from the detonation site.set it off underwater and you can again measure the pressure, the damage left behind, how much water is thrown in the air and so on.

If your test leaves a much bigger hole than expected, then you can compare your result to previous tests and work out a number.