What is the speed of the block (+ bullet) system immediately after impact?

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The discussion revolves around calculating the speed of a block and bullet system immediately after impact, where a 20-g bullet embeds itself in a 2.0-kg block of wood. The block moves 5 meters before coming to rest due to kinetic friction, with a coefficient of 0.25. Participants emphasize the importance of understanding conservation of momentum and energy principles in solving the problem. The conversation encourages users to attempt the problem independently and clarify specific points of confusion. Overall, the focus is on applying physics concepts to derive the required speed after the impact.
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Homework Statement



A 20-g bullet is fired into a 2.0-kg block of wood placed on a horizontal surface. The bullet stops in the block. The impact moves the block (+ bullet) a distance of 5 m
before it comes to rest. If the coefficient of kinetic friction between the block and
surface is 0.25, calculate the speed of the block (+ bullet) system immediately after
impact.

Homework Equations





The Attempt at a Solution

 
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Welcome to physics forums rdesio. You need to give the problem a try before we can help; or at least let us know what exactly you're having trouble with or confused about.

Some pointers:
What are the key ideas at play in this problem?
Why does the block and bullet stop at some point? What made them start moving in the first place? Is anything conserved throughout the process?
 
Try using the total energy before is equal to the total energy after equation.
 
Show some attempt......
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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Thread 'Minimum mass of a block'

Thread 'Minimum mass of a block'

Here we know that if block B is going to move up or just be at the verge of moving up ##Mg \sin \theta ## will act downwards and maximum static friction will act downwards ## \mu Mg \cos \theta ## Now what im confused by is how will we know " how quickly" block B reaches its maximum static friction value without any numbers, the suggested solution says that when block A is at its maximum extension, then block B will start to move up but with a certain set of values couldn't block A reach...
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