How Does Friction Affect Falling Objects?

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The discussion revolves around calculating the average force of friction acting on a hard hat dropped from a height of 22 meters. The hat, weighing 250 grams, reaches a speed of 9.0 m/s upon impact. Participants suggest using the work-energy theorem, where the work done by friction equals the change in kinetic energy plus the change in potential energy. The key equations involve understanding that the hat gains kinetic energy while losing potential energy. Ultimately, solving for the average force of friction requires applying the equation W = F x d, where 'd' is the distance fallen.
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Homework Statement


A construction worker at the top of a ladder drops her 250 g hard hat from a height of 22m. When it reaches the ground it is traveling at 9.0 m/s. What was the average fore of friction as it fell.



Homework Equations


Stuck here...


The Attempt at a Solution


Can't figure out what equations to use... Tried finding t, then using ft=mv and solving for t, but that does work.
 
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Use the work energy theorem.
 
Xisune said:
Use the work energy theorem.

Would you mind explaining buddy, kinda lost...
 
W = ΔEk + ΔEp

W is work due to friction.
ΔEk is the change in kinetic energy.
ΔEp is the change in gravitational potential energy.

In this case, the hat gains kinetic energy but loses potential energy, so ΔEk is positive, and ΔEp is negative.
 
KK I got that, but how would I go on to finding the force of friction?
 
W = F x d, you know what d is.
 
O I see now, so solving for F would give you the average force. True, thanks buddy mind taking a look at my other thread? Title is Momentum + Energy :)
 
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