Calculate the average net force acting on the bullet

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silje
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I have a physics problem and are woundering if someone can please help me!o:)
Here's the problem: A bullet of mass 20 g strikes a fixed block of wood at a speed of 320 m/s. The bullet embeds itself in the block of wood, penetrating to a depth of 6.0 cm. Calculate the average net force acting on the bullet while it is being brought to rest. (1.7 x 14^4 N)

would have been nice with the whole calculation.
Thanks! :!)
 
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silje said:
I have a physics problem and are woundering if someone can please help me!o:)
Here's the problem: A bullet of mass 20 g strikes a fixed block of wood at a speed of 320 m/s. The bullet embeds itself in the block of wood, penetrating to a depth of 6.0 cm. Calculate the average net force acting on the bullet while it is being brought to rest. (1.7 x 14^4 N)

would have been nice with the whole calculation.
Thanks! :!)
Trythe work-energy theorem, which states
[tex]W_{net} = \Delta KE[/tex]
What is the initial kinetic energy of the bullet just before it penetrates the wood? What is its final kinetic energy when it comes to a stop in the wood? What is the difference between the two energies? What is the definition of work?
 
Alternatively, you can use kinematics to determine the acceleration of the bullet (vf^2 = vi^2 + 2ad), then use Newton's 2nd Law to determine the force (F = ma).
 
thank you very much! =)