What Is the Initial Speed of a Bullet Fired into a Block?

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To determine the initial speed of a bullet fired into a block, the conservation of momentum principle should be applied after the bullet embeds itself in the block. The block's fall from the table introduces vertical motion, which can be analyzed using kinematic equations to find the time of flight. The horizontal distance traveled by the block after the impact is linked to the initial velocity of the combined block and bullet system. By calculating the horizontal velocity and relating it back to the bullet's initial speed, the problem can be solved. Understanding both horizontal and vertical motion is crucial for finding the correct answer.
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First post here on the forum, so excuse me for any mistakes.

A bullet of mass m is fired into a block of mass M initially at rest at the edge of a frictionless table of height h. The vullet remains in the block, and after impact the block lands a distance d from the bottom of the table. Determine the initial speed of the bullet.

No variables are given, the answer should be in the form of an equation.

I'm having a really hard time starting this problem, but am pretty confident that with a hint I could get it taken care of. I'm thinking that the conservation of momentum equation (Pi=Pf) will help determine the velocity of the bullet, but I'm not sure how to compensate for the block falling off of the desk. Maybe the laws of motion equation? (X=Xi+VixT+1/2AT^2)?

Any help would be appreciated. I have the answer from the book, but am not sure how to figure it out. Let me know if knowing the answer would help. Thanks
 
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You're absolutely right. Use the x equation to find the initial velocity of M and m (when they are together). Then relate that velocity to the initial velocity of the bullet before it hits the block. Is there a specific place where you have trouble? Don't forget that you have to consider the motion in the horizontal and vertical directions as the block and bullet are falling off the table.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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