Calculate the average net force acting on the bullet

AI Thread Summary
To calculate the average net force acting on a bullet that embeds itself in a block of wood, one can use the work-energy theorem, which relates net work to the change in kinetic energy. The initial kinetic energy of the bullet can be calculated using its mass and velocity, while the final kinetic energy is zero when the bullet comes to rest. The difference between these energies gives the work done on the bullet, which can be used to find the average net force. Alternatively, kinematic equations can determine the bullet's acceleration, which can then be used with Newton's second law to calculate the force. This approach provides a comprehensive method for solving the problem effectively.
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
W_{net} = \Delta KE
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! =)
 
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