hmm well, size and falling

Today as i walked my dog through my neighborhood, a thought that i have had a couple times came to me again as i saw squirrels playing in a tree.

lets say we have two tree that are the same size and a decent size too( height wise) and grass at the bottom.

if you had a squirrel in one
and a human in the other and both of them fell, who would be more hurt, the squirrel or the human?

what about with concrete at the bottom and not grass?
now what about if the fall is long enough for both to reach their terminal velocity?

always has interested me

 

I am pretty sure the squirrel would take in less damage. They have evolved to live in trees and survive falls, while humans have evolved to live on the ground.

 

Science is not a forte of mine so this is probably going to make me look like an idiot but here's what I THINK i remember from my high school days.

Don't items from the same distance fall at the same rate of speed regardless of their rate due to gravity?

Hypothetically, they should both be hurt the same because of their speed BUT, you would have to look at their bone structure, how flexible they are, if they land on their side, head, stomach, back, etc.

I feel as if the human would be hurt more since I think squirrels can turn in midair just like cats can.

 

More mass = more force

l2physics.

"hurt" is a bad term but the human would hit the ground "harder" in a sense.

 

That's like saying a feather and an elephant would fall at the same speed if you dropped them off the empire state building.

Anyways, it's simple physics, a human weighs more and therefore would have a "heavier" impact then the squirrel.

 

he is right though, except the feather has wind resistance so it would actually not be something good to compare it with

but an elephant and a watermelon dropped from the empire state building, they would reach the ground at the same time.

 

The elephant has much more mass then a watermelon, and therefore would fall at a much faster rate. The only situation in which that would not be true is if there was no gravity/wind resistance/ or any other outside factor in the equation.

 

What kind of hefty watermelons are you eating?

Here is a more simple summary.


Elephant - Fat
Watermelon - Not as fat, but still chunky

Fat = More weight = More force when falling, cause le gravity

 

nooooo. If two things fall from the same height, with no air resistance to them, they will reach the ground at the same time. Wether it is a marble or a 1 ton ball of steel

 

No. Mass has no effect on free fall at all.

Consider a flat piece of paper, dropping it would cause it to float to the ground slowly. Now, crumple the piece of paper and drop it. It falls promptly to the floor. You didn't change the mass, you changed the surface area, which changed free fall speed.

 

Surface area is only one factor in it.

You have to be retarded to think that a piece of paper and a piano are going to fall at the same speed.

 

http://www.youtube.com/watch?v=Z789eth4lFU

Have you EVER taken physics?

 

Things fall at the same rate... LOL this the BASICS of physics. ( excluding wind resistance ect. )

Gravity accelerates at a constant rate.
weight only applies to force not acceleration of free fall.

honestly use google.

 

finally someone to help me explain this ;P

 

Surface area is the ONLY significant factor into it unless you are talking about the grand macroscopic topic.

Gravity is a force between two objects which draws them together. and is represented by GMM/R(squared). Of course the mass of the earth between two objects on it is going to be so gigantically huge that the earth will never move too much however all objects that are thrown away do SLIGHTLY pull the earth towards them.

A paper piano and a real piano would fall at exactly the same speed despite the significant difference in mass, similar to how a watermelon and any weight bowling ball fall at the same speed even though the masses are different.

However if you were to compare two different stellar objects like a dwarf planet on one side and an asteroid on the other falling into earth from the same distance at the same speed the dwarf planet would fall "faster" due to it actually pulling the earth away from the asteroid because of its significant mass with respect to the earth.

With regards to the original OP its more to do with evolution than anything, we evolved to not deal with large impacts on limbs on a regular basis while a flying squirrel does it commonly.

 

Wow, I can't believe people really believe that mass makes a big difference in free fall motion. Galileo demonstrated this years ago. http://www.grc.nasa.gov/WWW/k-12/airplane/ffall.html

The only thing that could affect the motion would be air resistance, which is largely related to the shape/surface area of the object (hence why a feather takes longer to fall to the ground than a ball). But for the human and the squirrel, considering they are both falling from such a small distance, air resistance is negligible.

Now to answer the first part of your question, the human will most certainly feel more force exerted upon him/her. It's simple Newtonian physics - every action has an equal and opposite instantaneous reaction. Both the human and the squirrel fall according to Newton's 2nd law - the equation 'F=ma'. The value 'a' is constant for both - however, the mass of the human is much greater than the mass of the squirrel. Hence, the human exerts a greater force on the floor (this force is a consequence of mainly gravity). As a result of Newton's 3rd law, the floor exerts this exact same force to the human, which happens to be much greater than the force that would be exerted on the squirrel.

Now, whether or not the human feels more pain or not is entirely up to his/her strength/tolerance for pain.

However, a very good question of yours is, "Why does falling on concrete 'hurt' more than falling on grass?"

This actually has to do with momentum. Now for both surfaces, your change in momentum (which is the product of mass and velocity) will not change. However, as concrete is a much harder surface than grass, the time you are in contact with the concrete will be less than the time you are in contact with the grass.

I'm sure you know the following variation of Newton's 2nd law, being F=delta p/delta t, where F is the net force, delta p is the change in momentum (impulse), and delta t is the change in time. We can rearrange this equation to give the following: delta p = F*delta t. As you can see, since we know that the change in momentum is constant (delta p), that means that if we were to lower the value of delta t, the value of F would have to increase as a result of this. Hence, F would be larger for a concrete surface, where the time of contact is smaller than that of grass. As a result of this larger force being exerted on the ground, the ground will have to exert the same force onto the falling object, in accordance with Newton's 3rd law.

 

Well I've seen squirrels fall from trees and die instantly. As where I would probably fall from the same tree and be hurt, but not as her as the squirrel. We don't even have to compare the two for evolutional purposes or adjustments. I know that squirrels I've evolved to take the damage from falls but I do believe humans aren't as delicate and small and have way more muscles and fat than squirrels. Just take out the rest of the factors such as how you land when you fall and other factors like that and I think a squirrel would die if it fell, and a human wouldn't

Sorry if this has errors. Did it on my phone

 

While all objects fall at the same speed, the force with which they hit the ground is dependent on their mass.
The human would hit the ground with higher force than the squirrel.
For example, if you dropped a fairly large ball of steel and an equally sized giant cheese puff onto sand, they would fall at the same speed, but the ball of steel would create a larger crater.

Yes, but for example throw an ant or cockroach off a tree. It won't even get hurt since it hits the ground with almost no force

 

what you are forgetting to include is the gravitational attraction between the man and the squirrel, because you said there are two trees they are being dropped out of at the same time.
Here to work out the acceleration due to the two bodies attracting each other I have used F=(GMm)/R^2 and roughly guessed the mass of the squirrel and the man.

using vectors I then showed how this new force effected how fast the two bodies would fall.

I hope my scientifically rigorous explanation is clear, the squirrels will take much more damage in this situation. (we are assuming that quantum tunnelling does not take place, and both bodies collide with the ground.)

edit:You really took this seriously?... Was more a joke at some of the explanations in this thread.

 

Incorrect.

Seriously use Google and look up some of the laws of physics.

The gravitational attraction between the human and squirrel is so small you could hardly measure it. How hard they hit the ground is dependent upon force.