How far do acorns drift in the wind?

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SUMMARY

The discussion centers on the physics of acorn drift influenced by wind, specifically under the assumption of a wind speed of 25 m/s and a horizontal direction. Participants emphasize the importance of relevant equations, such as time of fall calculated with t = √(2h/g) and the force of wind using F = 0.5 * p * v^2 * A * Cd, with a drag coefficient of 1.2. The conversation highlights the need for participants to demonstrate their problem-solving efforts to keep the discussion active. Key calculations include determining time of fall and the effects of wind force on acorn drift.

PREREQUISITES
  • Understanding of basic physics concepts, including free fall and drag force.
  • Familiarity with relevant equations such as t = √(2h/g) and F = 0.5 * p * v^2 * A * Cd.
  • Knowledge of terminal velocity and its comparison with wind velocity.
  • Basic algebra skills for solving equations related to motion and forces.
NEXT STEPS
  • Research the implications of air resistance on falling objects.
  • Learn how to calculate terminal velocity for different shapes and sizes.
  • Explore the effects of varying drag coefficients on object motion.
  • Investigate the relationship between wind speed and object displacement in physics.
USEFUL FOR

Students studying physics, educators teaching mechanics, and anyone interested in the dynamics of falling objects and environmental influences on motion.

nick-metersecondsq
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New user has been reminded to please always show their work on schoolwork problems.
Homework Statement
we live under a lot of trees, including great oaks. How far can wind carry a falling acorn?

acorn mass: 4.5g
acorn size and shape: r=3cm (assuming sphere)
height of fall: 27m
air density 1.225 kg/m3
Relevant Equations
this is open
this one is our extra credit problem with no instructions. just creative thinking.
 
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It seems you would need to assume a wind speed and direction.
 
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Acorns rely on ground transportation (mostly squirrels and chipmunks).
When they drop, they generally stay within the trees immediate shade/shed zone.
 
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sorry I left that off. speed is 25 m/s and direction is parallel to the ground.
 
So what attempt have you made to solve the problem yourself? We don't spoon feed answer, but rather help people who are trying to help themselves.
 
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Thread closed for Moderation...
 
Thread is reopened provisionally.

@nick-metersecondsq -- Please show your best efforts to work on this problem so that the thread can remain open. It is important for you to list the Relevant Equations involved.
 
nick-metersecondsq said:
sorry I left that off. speed is 25 m/s and direction is parallel to the ground.
Please post a complete statement of the given problem. There are relevant equations, so please post what you think they might be and tell us why. We need to understand the problem as well as your attempt at solving it.
 
Mister T said:
It seems you would need to assume a wind speed and direction.
berkeman said:
Thread is reopened provisionally.

@nick-metersecondsq -- Please show your best efforts to work on this problem so that the thread can remain open. It is important for you to list the Relevant Equations involved.
so far I know t = √(2h/g gives me time ... so t=sqrt(2(27)/9.8 = 2.35s

Force of wind is F = 0.5 * p * v^2 * A * Cd. i'm assuming drag coeff of 1.2?

F=2.6
mass of wind = density * area = M= 1.229 kg/m3 * (3 pi r2 = .000084*1.229= .00010

I need F=ma, solving for A since I have t and need distance.
but maybe my algebra is wrong, but that gives me A=F/m = 206000 ms2 (which is bonkers).
and that's where I'm lost.
 
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nick-metersecondsq said:
so far I know t = √(2h/g gives me time ... so t=sqrt(2(27)/9.8 = 2.35s
That is with the assumption of zero air resistance.
nick-metersecondsq said:
Force of wind is F = 0.5 * p * v^2 * A * Cd. i'm assuming drag coeff of 1.2?
That is with the assumption of non-zero air resistance.

Maybe you could try computing terminal velocity and compare that with the landing velocity under the assumption of free fall.

Or maybe you could compare terminal velocity with wind velocity.
 

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