Momentum, Gravity and Friction Mixed Problem

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Homework Help Overview

The problem involves a bullet being fired into a wooden block, resulting in an inelastic collision. The scenario includes concepts of momentum conservation, friction, and projectile motion, as the block may slide off a table after the collision.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants discuss using conservation of momentum to find the initial velocity of the block after the bullet embeds in it. There are questions about how to determine the block's motion after the collision and the effects of friction on its movement. Some participants express confusion about the time variable in their calculations.

Discussion Status

Some guidance has been provided regarding the use of momentum conservation and subsequent calculations involving friction and projectile motion. Multiple interpretations of the problem are being explored, with participants sharing their reasoning and seeking clarification on specific points.

Contextual Notes

Participants note the absence of certain variables, such as time, which complicates their calculations. There is an emphasis on deriving equations and understanding the relationships between the forces involved.

Haroon
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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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