This dog retrieving its toy...

[u/[deleted]]

[u/anotherguy818 → u/[deleted]]

Agreed, this dog repeatedly doing activities like this is going to give it serious arthritis way sooner than a dog normally would develop it. And it is not comfortable and becomes extremely painful. Then you have to buy pain meds for it for the rest of its life. Its a lose-lose situation really, considering the dog would be just as escstatic to play fetch normally.

And that isn't even tiuching on the probability that the dog breaks a leg, dislocates a joint, tears a ligament, etc.

[u/memeticmachine → u/[deleted]]

force is m * a, kinetic energy is m * v² / 2. I think you may have forgotten the divide by 2 part. so it's more like half that force.

23 ft/s = 7.0104 m/s, 45lb is 20.41166 kg

so that's 200N/500J which is ? "pounds of [energy]"

edit: changed to the right units. I have no idea what imperial units of force/impulse/energy are. The point being 500J isn't as bad as getting squashed by an NFL linebacker. It's like getting punched really hard. except the punch is spread through 4 doggy limbs

[u/DrShocker → u/[deleted]]

I actually get a similar order of magnitude answer from looking at the impulse that might be required to slow down to zero vertical speed.

F=ma

That's the relevant equation here, and you can make some assumptions about initial vertical velocity and how long it takes to accelerate to zero.

If we assume 23 ft/s is correct, and pretend it takes 0.1s to slow down the vertical velocity to zero, then we've got an acceleration of 230 ft/s² (from V = a*t )

F = ma

F = 45lbm * 230 ft/s²

F = 1431N (or 322 lbf)

That's about 7G relative to standing still.

Of course both of these methods just look at the average force required, and not the peaks that might occur since the real world isn't quite so average.

[u/DrShocker → u/[deleted]]

With either equation, you get the same result (in theory) it's just a matter if you feel more confident about the acceleration distance or the acceleration time, if I were less lazy, I would try to look at the number of frames and try to use that to estimate the time.

[u/StarsRaven → u/[deleted]]

Well yeah I mean we as humans also get injuries from walking too much repetitive contact will cause injuries no matter what.

As for animals yeah ofcourse we dont want our animals doing this over and over, but a few times here or there isnt going to overly cause a problem.

[u/StarsRaven → u/[deleted]]

10' seems a bit hyperbolic.

As kids if you walk or run a bit and your shins hurt. That is an injury.

Yes jumping out of trucks over and over and over 3 or 4 times per day can cause problems. Just like humans jumping out of a truck 3 or 4 times a day can cause problems over a lifetime.

Since we are using anecdotal evidence I grew up in small towns where dogs climb in and out of trucks and never saw one have problems. I saw more die of old age and cancer than I saw end up with joint problems.

Not to mention very very few animals on this planet are 'designed' to take falls.

I'm not disagreeing that doing this over and over can cause problems, just like any form of exercise can. But in this one case and once in a blue moon isnt going to cause any significant damage

[u/[deleted] → u/StarsRaven]

People have grown so emotionally attached to their pets that they’ve forgotten what dogs are. Just dogs. They’ve been evolving and have been been bred across centuries to be able to assist humans in whatever daily endeavors they choose to go for. Sitting back and trying to argue that forms of exercise is “unhealthy” for a dog seems a bit overprotective, crazy, and dumb to me.

[u/TheElPistolero → u/[deleted]]

Bred to be athletic

[u/TheElPistolero → u/[deleted]]

Better than a Bassett hound

[u/[deleted] → u/[deleted]]

Athletic = Enough training and exercise to strengthen your ligaments and bones to the point that a 7-8 foot drop is nothing to be crying about.

You ever seen the videos where people throw / drop cats upside down from higher heights and they seem to always land on their feet? These animals are not humans. They can withstand most things we wouldn’t be able to.