fidgewinkle wrote:There are three factors which determine the amount of force applied to a falling object when it hits the ground.
Speed
Hardness of the ground
Mass of the object
Speed is mostly dictated by the height from which the object fell, as a ping pong ball falls at roughly the same speed as a brick. So assuming it is a free fall, the speed is based upon the height fallen from. There is terminal velocity to contend with, but that is more of a cap on damage than anything else.
only in a vaccum will a pingpong ball fall at the same speed as a brick. That said terminal velocity is reached after only about a 400 foot drop for person shaped objects (throuhg normal atmosphere). Terminal velocity is simply where the slowing effect of air friction exactly matches the acceleration of gravity. At very high altitudes the air is VERY thin and offers very little resistance, so little that a person can actually fall at or over the speed of sound.
Saying what you fall on doesn't matter is like saying playing tackle football on pavement is the same as playing on grass. It isn't true. Hardness of the ground affects how quickly the object stops, which increases the amount of force exerted upon it. Going from 10m/s to 0m/s in 1s results in a deceleration of 10m/s/s while doing so in 0.01s results in a deceleration of 1000m/s/s. Since force = mass x acceleration, the second situation will result in 100x the force.
Actually at the speeds at which you will impact at terminal velocity for a human the surface doesnt really make a difference. Sure the math might say that the decleration upon hitting concrete from 400' is 356 Gs (just made that up) and that hitting water from 400' is 173 Gs (also made up) but the relevance of it is moot because either way the person is dead. Your tackle football on pavement versus grass analogy is not apt as the forces we are dealing with are much higher and are deadly (to SDC things despite the surface impacted...MDC however is a nother ball of wax entirely)
Since force = mass x acceleration, mass is a big part of the equation and should be taken into account when falling damage is calculated. The adage "the bigger they are, the harder they fall" is true. Something that weighs 10x as much should take 10x the damage when it hits the ground. This leads to the following conclusion:
Agreed. This is a valid point for the object impacted as well as the object falling. We can see this in action with projectiles that travel at the same velocity but different weights... heavier is more damaging. For the damage to the object look at an adult versus a toddler falling on thier butt... tot takes no damage while the adult can break thier tailbone or atleast severly bruse thier glutes.
But again we are talking about a person falling at terminal velocity... they are dead weather they are a 20 pound tot or a 200 ound man. Now would a 200 lb MDC "man" die if impacting the ground at terminal veloicity?
1d6 SDC per 10ft is a fine rule for human weight objects. However, bigger objects like that tank are going to take a whole lot more damage. I would divide weight by about 200 lbs and multiply the damage by that when calculating damage. Therefore, a forty ton tank that falls 200ft is going to take 20d6SDC x 400 damage, or 8d6x10 MD. That would destroy a current day tank. A RIFTS tank would probably survive because it is made of stronger materials. Of course, the crew inside would take falling damage of 20d6 SDC and could take additional damage from objects inside of the tank.
The whole 1d6 per 10 feet is silly because of terminal veloicity and besides this is meant for "soft" SDC falling objects not "hard" SDC falling objects or MDC (hard or soft) objects.
Drop a 2" diameter steel ball from 400' feet into a salt flat, did it get destroyed, dented, one sided flatened, damaged at all? No.
Drop a 2" ball of balistics gel from 400' onto the same salt flat, did it get destroyed? Yep.