Momentum, Gravity and Friction Mixed Problem

AI Thread Summary
The problem involves a 15g bullet fired at 750m/s that embeds in a 1250g wooden block, which is initially at rest on a table. Conservation of momentum is used to determine the initial velocity of the block after the bullet embeds itself, leading to an inelastic collision. The next step is to assess whether the block will slide off the table by comparing the force of friction to the block's acceleration. If the block does slide, its horizontal distance from the table base when it hits the floor can be calculated using projectile motion equations. The discussion emphasizes the need for clarity in deriving equations and applying kinematic principles.
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Homework Statement



A 15g bullet is fired from a gun, leaving the gun with a muzzle velocity of 750m/s. It hits and sticks in a 1250g wooden block. The block is on a table 5.0m away from edge. The table is 1.1m above the floor and between the block and the table surface constant of kinetic friction is 0.50. Will the block slide off the table and if so what will be the horizontal distance from the block to the table base when the block hits the floor?

Homework Equations



Momentum equation , dynamics, friction and Fg

The Attempt at a Solution



so basically we find the intial velocity of wooden block with the help of given data of bullet b/c momentum has been conserved. so block is moving. or maybe m wrong. this question has confused me. suppose the block is moving then how do we know how far it will go. I have some idea but how do i derive equations and find the answer,
Plzz help. Its very important.
 
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use conservation of momentum.
after the bullet sticks it has the same velocity as the block and hence it is a inelastic collision.
calculate final velocity of block and bullet.

That becomes the initial velocity for the block.

Now see if the mass*accln of block is greater than frictional force or not.
if yes...then:
Use force equation to calculate accln of block.

Now calculate its velocity after it reaches the edge of the table i.e. travels 5m.

Then take the block to be a projectile to be fired horizontally and calculate the range.

HERE take vertical height as height of table i.e. 1.1m
 
i have no delta(t) here?
how i u suppose to sub it in equation?
 
i think i got it, using kinematics eqs.
but if u want to explain it to me to clarify then it would be very nice. thanks. :D
 
sure frnd but first show me ur work how u r proceeding...
 
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