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Old 11-17-2010, 07:18 PM   #1
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Hey guys, help needed, here goes

A meteor with a mass = 1Kg moving at 20km/s collides with jupiter's atmosphere. the meteor penetrates 100 km into the atmosphere and dsintegrates. What is the average force on the meteor once it enters Jupiter's atmosphere (ignore gravity)?

a) 2*10^3 N
b) 4*10^3 N
c) 8*10^3 N
d) 2*10^5 N

thank you
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Old 11-17-2010, 07:38 PM   #2
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A?
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Old 11-17-2010, 07:51 PM   #3
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that's correct, But i don't get it

1/2mv^2= F*d
1/2 * 1 * (20)^2 = F * 100km

200 = F* 100km
F= 200/100
F= 2N

what am I doing wrong????
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Old 11-17-2010, 07:57 PM   #4
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Convert Km to m in both the velocity and the displacement.
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Old 11-17-2010, 08:06 PM   #5
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DUH!!!! I AM SO RETARDED! thank u so much
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Old 11-18-2010, 10:22 AM   #6
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Don't worry about it haha. That has happened to me about 1 million times.
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Old 06-01-2012, 10:19 AM   #7
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hey I know this was posted a while back, but I am hoping someone can clarify this problem a little for me. I thought that you would use the equation Fdcos(theta) and cos of 0 is just one so then I thought this was set to equal the change in kinetic energy plus the change in potential energy so it would be F*d = delta K + delta U....how come above you just did F*d = delta K...where did the change of potential energy go?

thanks!
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Old 08-02-2012, 02:34 PM   #8
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Quote:
Originally Posted by panda2queen View Post
hey I know this was posted a while back, but I am hoping someone can clarify this problem a little for me. I thought that you would use the equation Fdcos(theta) and cos of 0 is just one so then I thought this was set to equal the change in kinetic energy plus the change in potential energy so it would be F*d = delta K + delta U....how come above you just did F*d = delta K...where did the change of potential energy go?

thanks!
the question says to ignore gravitational force
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