1. The problem statement, all variables and given/known data For a project I am doing I have to disprove something I see in a video. In the video, a person falls into a cart full of hay from a height that is irrelevant. What I know is that the person's speed at the top of the leaves is given by v (I have the actual number for v but I would rather see it done theoretically). The person's speed changes from v to 0 in time t. Given that the person's mass is m, I need to determine whether this collision would be lethal. In the video the person survives but I need to mathematically and statistically prove that he wouldn't survive this collision. Is there a standard way to determine whether a certain impulse, etc. will kill an average person? 2. Relevant equations ΔP=FavgΔt = mΔv 3. The attempt at a solution I wound up calculating that the average acceleration (or "g-force") was about 75 g, and this acceleration occurred over roughly 0.033 seconds. The impulse would be m*a*t which would be 85 kg * (75 * 9.8) * 0.033 = 2061.68 N*s. I know I need to use this impulse, the force, or the acceleration, and I have done so, but my concern is, I have no real standard for figuring out whether the collision will be lethal. I have seen plenty of documents online but they only refer to things like "humans can withstand sustained g-forces of yada-yada-yada" or "humans can take instantaneous g-forces of yada-yada-yada". The trouble is, instantaneous is too vague, and sustained is not what I am looking for.