The destructive force of a 1,000kg boulder hurled by a catapult

[Journeyman]

Homework Statement: Could be silly to some, but I am writing a short story and hope someone can help.
Relevant Equations: I am clueless, forgive me.

Hello all! I tried asking Bing/CoPilot, Google, and visited some medieval war machine forums, but could not find something that could help me with my question. I am in the midst of writing a short story and being a big fan of the Dark Millennium of Warhammer 40,000 books, I understand the rather effective fiction and dramatic effect of having things being much bigger than they usually are when it comes to destructive force and overwhelming annihilation.

I understand that trebuchets with their heavy counterweights can hurl massive boulders to siege castles. I have read that though the average weight of a rock boulder hurled is usually around 80kg to 120kg, and they were highly effective in siege warfare, and going any heavier than that is highly inefficient and overkill. I have read that they can toss 250kg, 500kg, and even up to a tonne.

However, I would like to be able to visualise just what would happen if a 1,000kg (1 tonne) rock boulder is tossed into a unit of troops. What would happen based on the laws of physics, joules, force, etc. I tried one of the online formula calculators but I totally have no idea how to use them. I understand my question could be vague, and do not have any parameters such as speed, velocity, angle, etc. to supply you, but I guess a general idea of what would happen to the mass of troops would do. For example, would the rock just land into the ground and flatten whatever is under it? Or would there be a massive impact so destructive that it would create a crater and a mini explosive and concussive force that hurls men about and break bones?

Forgive me as I am an arts student and do not have a shred of understanding of physics. Thanks in advance!

 

[Drakkith]

For the size of rocks you're talking about, an 'impact' would mostly just crush those it directly impacted. Some would be hit as the boulder bounced and tumbled into them, seriously injuring or killing them, and that's about all. It might scatter some mud or dirt around from impacting with the ground, but those effects depend on exactly what the terrain is like. A boulder landing in a bog is somewhat different than a boulder landing in a grassy field, but mostly in whether or not it bounces and rolls. Regardless of terrain there wouldn't much if any concussive 'blast', as there just isn't enough energy being imparted into the air.

To get seriously different results the boulder would need to be travelling at MUCH higher velocities than a simple catapult or trebuchet can produce. And if you have the technology to launch a 1-ton boulder at mach velocities you probably have better weapons like artillery and missiles.

 

[Hill]

Like this cow.

 

[Astronuc]

However, I would like to be able to visualise just what would happen if a 1,000kg (1 tonne) rock boulder is tossed into a unit of troops. What would happen based on the laws of physics, joules, force, etc.

One can find videos of boulder(s) rolling down hill, some going airborne, and smashing structures. Depending on the type of rock, the rock may break apart into smaller projectiles. The type of damage depends on the mass and velocity.

https://www.vice.com/en/article/5dbj85/landslides-kills-9-tourists-in-terrifying-video-india

When a boulder crashes into a home
https://www.nbcnews.com/news/us-new...er-crashes-honolulu-home-nearly-str-rcna68351

Boulder rolled down a hill breaks a tree (don't do this)


One can find examples of houses in Canterbury, NZ, where boulders were loosened on hillsides and crashed into houses.