Solving for Meteor's Speed: Unknown Speed!

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The discussion centers on calculating the speed of a meteor that crashed into the Earth, given its mass, depth of penetration, and the resistance force of the ground. The user initially struggles with the concepts of potential and kinetic energy, as well as the relationship between force, distance, and work. After some guidance, they correctly calculate the work done by the resistance force and apply it to find the meteor's speed. The final calculated speed of the meteor is approximately 1016.58 m/s, with a reminder to use mass in kilograms rather than Newtons for accurate calculations. The conversation highlights the importance of understanding the physics principles involved in such problems.
DaxInvader
Unknown Speed!

Hi all, I've got this problem in my physics class I can't figure it out. Iv'e changed the values because I only wan't to know How we can solve this..

Here it goes:

I have a 400 g (3,29 N) Meteor that crashed in the Earth surface and reach a depth of 1.7 m . The scientist say that the ground had a resistance force of 1,0 x 10^6 N.

(We ignore the air's friction.)

What was the meteor's speed?


It's all I've got.

Iv'e done a graphic on paper whit vectors But I don't quite get the methos of doing it.

Else.. I tried Caluculating the potiential energy (Ep = mgh) but I don't have the height.. Neither de speed for the Kinetic energy (Ek = 1/2 m v^2)

Bah.. Help me out! :P:P
 
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Do you understand the relationship between force, distance, and work?

W = F*d

- Warren
 
OHHH ! nevermind.. I get it!I will start working on it.
 
Here is what I have done:

W= Fr * Delta Sr
W= 1000000 N * 1,7 m
W= 1700000 J

Ek = 1/2 * m * v^2
1700000 j = 0.5 * 3,29 N * v^2
1033434,65 j = v^2
1016,58 m/s = V

Meteor's speed is 1016,58 m/s
 
Be careful with your units. Mass should be in kilograms, not in Newtons. Otherwise, yes, you have the right idea.

- Warren
 
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