B An explosion under a pile of timber and rocks

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In the scenario of an explosion under a pile of timber and rocks of equal weight, the timber, having a lower density and greater cross-section, will be accelerated faster and ejected higher than the rocks. Consequently, the timber will take longer to return to the ground, while the rocks will land first due to their higher density and lower elevation after the explosion. The discussion emphasizes that the initial velocity of each piece depends on the energy distribution from the explosion. Additionally, the question lacks specificity, as the outcome varies with factors like the angle of ejection and air resistance. Ultimately, the mass with the smaller vertical component of velocity will land first, assuming air resistance is ignored.
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There is a pile of rocks and timber, all the same weight, under it is an explosive device after the explosion the pile is ejected in the atmosphere, which timber or rock will land first?
 
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The timber has a lower density, so a greater cross-section for the same weight, and will be accelerated faster than the rock. The timber will go higher and further, therefore it will return to the ground later. The rock will tend to land first.

If you empty a tip truck, or excavator bucket, that contains mixed timber and rock, the rock will tend to exit first, followed by the timber.
 
Simon Peach said:
There is a pile of rocks and timber, all the same weight, under it is an explosive device after the explosion the pile is ejected in the atmosphere, which timber or rock will land first?
Your description is vague and does not have a unique answer. To make a meaningful comparison, you have to specify what else is the same other than the weight (or mass.) A pile of mixed rocks and pieces of wood, all of the same mass, sitting on top of an explosive device will scatter in all different directions when the explosion occurs. Furthermore, any particular piece will have initial speed that depends on its share of the total energy released in the explosion.

As stated, your question has one answer, "the mass that has the smaller vertical component of velocity will land first because it spends less time in the air." That's ignoring air resistance.
 
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