Tree Cutting Word Problem: Why Does the Short Tree Hit the Ground First?

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In the discussion about why a short tree hits the ground first when both a tall and short tree are cut simultaneously, participants explore the effects of gravity and the distance each tree's top must travel. The conversation highlights that the height of the tree influences the time it takes to fall, as a taller tree has a greater distance to cover. Some contributors emphasize the importance of using equations to gain a quantitative understanding of the problem, while others argue that qualitative insights can still be valuable. The need for mathematical analysis, such as free body diagrams and conservation of energy, is underscored for a comprehensive solution. Ultimately, the discussion reveals that while qualitative reasoning can provide some answers, a deeper understanding requires mathematical formulation.
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Homework Statement



a tall tree and a short tree of the same mass density and width are cut at the base at the same time. why does the small tree hit the ground first?

Homework Equations



none. its a word problem

The Attempt at a Solution


gravity id pushing in different ways?
 
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simple hint: How far does the top of the tree have to move for a small and for a large tree? could a tree that's twice as tall move twice as fast?

harder: replace the tree with a pole with length l. suppose it's at an angle A from the vertical. Draw a free body diagram and find all the forces. You could also find the speed at angle A with conservation of energy. Solve the differential equation for the movement of the tree. (probably needs to be done numerically)
A problem is what the initial angle, or the initial speed of the tree would be.
 
saying that a word problem has no relevant equations is just silly. If there are no equations, then you are not going to get any answer.
 
phinds said:
saying that a word problem has no relevant equations is just silly. If there are no equations, then you are not going to get any answer.

really? because the answer above you helped me and they didnt use any equations?
 
physicsgurl12 said:
really? because the answer above you helped me and they didnt use any equations?

Yes, you're right, of course. I should have said, you won't get a quantitative answer. You'll notice that willem DID talk about equations. To really understand what's going on, you need the math.

EDIT: And it IS silly to say that a word problem has no equations. If you don't understand that, you aren't going to get far in answering word problems.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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