In this video, some Australian knuckleheads are trying to catch apples dropped from a helicopter at 500 feet (about 150 meters). They don’t wear helmets.
Neither physics nor orthopedics nor botany are my strong suits, but from where I sit a conk on the noggin from an apple moving at that speed is going to, at the very least, leave the patient with a bruise, possibly bleeding and even a concussion. Hell, for all I know they could be risking getting knocked out cold or even brain damage.
According to this website, the velocity of a baseball dropped 500ft is about 80-90 miles per hour. (the blue line of Fig. 3) Terminal velocity appears to be about 100mph.
I’d assume an apple to be similar enough to a baseball to fit a similar velocity profile, at the maximum, and likely be somewhat slower IRL due to an irregular shape.
Given that apples aren’t quite as hard as baseballs, I’d expect the damage from a hit to be less, but not that much less. So, about the same as getting hit in the head with an 85mph fastball.
But an apple deforms on impact much more than a baseball. Some of the energy is going into squishing the apple and probably breaking it into several pieces. I think the impact to the head would be much less than that of a baseball.
Depends when, I’d rather get beaned in the Deadball Era. This brought up an odd memory, the old original Bill Cosby show in the 60s where someone claims they can catch a baseball thrown off the highest building in town. The guy ends up with his hands bandaged up. But there are some stories of baseball catches from great heights out there. Don’t know if anyone got one in the head, but batters have suffered serious career ending damage from getting hit in the head, and batted balls have killed people (check the disclaimer on your ticket folks).
ETA: I know the Dead Ball concept is controversial, don’t make a big deal about it.
Being whacked in the head by anything - fruit, game balls, fists, feet, etc - is usually not a good idea if continued brain function is your goal. See if your insurance covers head-whacking. Assume that 50% of kinetic energy is expended in apple-squishing when it hit your head. That’s like being beaned (sans batting helmet) with a hardball going only 45 mph. Do you feel lucky? Here, sign this disclaimer first.
I stayed at a Central American guesthouse with big honking avocado trees out back. I set a lawn chair into the shade. Another guest warned me to move away. Just then a 20-pound avocado fell to earth about ten feet from me. I quickly left the fall zone.
At that speed it might not fracture your skull like a nice hard baseball could, but the momentum transfer can still severely jar your skull, potentially inducing a concussion.
Even if you replace the apple with a water balloon, it can still do major damage. Note that people who jump from the Golden Gate Bridge suffer massive blunt trauma upon impact with the water.
But rather less than a baseball will, because a baseball will bounce, doubling the momentum transfer, and an apple will shatter, halving the momentum transfer. So lets say 80%.
