- #1
get_rekd
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A 0.25 kg pine cone falls from a branch 20 meters above the ground.
a) What speed would it hit the ground if the air resistance could be ignored?
I am not too sure how to do this but this is what I've got so far:
m=0.25
g=9.8 m/s^2
F=2.45 J
h=20 m
Ep=(0.25kg)(9.8m/s)(20m) Ek=1/2mv^2
=4.9J 4.9J=1/2(0.25kg)(v^2)
2(4.9J=1/2(0.25kg)(v^2))
9.8J=(0.25kg)(2v^2)
-0.25 -0.25
9.55J=2v^2
------------
2
4.775 = v^2
root 4.775 = 2.2 m/s = v ?
is this even close to correct. I think I am doing something wrong
a) What speed would it hit the ground if the air resistance could be ignored?
I am not too sure how to do this but this is what I've got so far:
m=0.25
g=9.8 m/s^2
F=2.45 J
h=20 m
Ep=(0.25kg)(9.8m/s)(20m) Ek=1/2mv^2
=4.9J 4.9J=1/2(0.25kg)(v^2)
2(4.9J=1/2(0.25kg)(v^2))
9.8J=(0.25kg)(2v^2)
-0.25 -0.25
9.55J=2v^2
------------
2
4.775 = v^2
root 4.775 = 2.2 m/s = v ?
is this even close to correct. I think I am doing something wrong