Table cloth pulled from underneath a block?

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The discussion revolves around a physics problem involving a block on a tablecloth being pulled horizontally. The key questions are determining the block's velocity when it first contacts the table and how far it slides before coming to rest. Participants suggest starting with a Free Body Diagram to analyze the net forces acting on the block and applying Newton's second law to find acceleration. The time the block remains on the cloth is calculated, which is crucial for solving the problem. The conversation emphasizes understanding the physics concepts rather than just seeking direct answers.
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Homework Statement


A very small block (mass "m") is at rest on a tablecloth on a flat table. the block is 80 cm from end A of the tablecloth. Suddenly, end B of the table cloth is pulled horizontally with speed Vo = 1.5 m/s. the block immediately slips on the cloth and continues to do so until the end of the cloth passes under it. Then the block slides on the table until it comes to rest. (mu) = 0.1 between the block and the table and between the block and the cloth.

a) What is the velocity of the block when it first makes contact with the table?

b) How far from its initial position does the block finally come to rest?


Homework Equations




Vertically

Fnet=ma=N-G

Horizontally

Fnet=P-Ff

Ff=(mu)N

N=mg

The Attempt at a Solution



time before cloth is out from under is 0.8/1.5 seconds


I have no clue where to go on this. if anyone could give me pointers on where to go with this question would be extremely appreciated. I don't want the work done for me just an explanation on how to go about this question.

Thanks!
 
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Start by drawing a Free Body Diagram of the small block to determine the net horizontal force acting on it while the tablecloth is being pulled. Then think Newton 2 to determine its acceleration, and it's speed and distance moved based on your time calculation for the length of time it is in touch with the tablecloth. Then repeat this calculation in similar manner to determine the answer to part b.
 
draymire said:

Homework Statement


A very small block (mass "m") is at rest on a tablecloth on a flat table. the block is 80 cm from end A of the tablecloth. Suddenly, end B of the table cloth is pulled horizontally with speed Vo = 1.5 m/s. the block immediately slips on the cloth and continues to do so until the end of the cloth passes under it. Then the block slides on the table until it comes to rest. (mu) = 0.1 between the block and the table and between the block and the cloth.

a) What is the velocity of the block when it first makes contact with the table?

b) How far from its initial position does the block finally come to rest?


Homework Equations




Vertically

Fnet=ma=N-G

Horizontally

Fnet=P-Ff

Ff=(mu)N

N=mg

The Attempt at a Solution



time before cloth is out from under is 0.8/1.5 seconds


I have no clue where to go on this. if anyone could give me pointers on where to go with this question would be extremely appreciated. I don't want the work done for me just an explanation on how to go about this question.

Thanks!

Wow, estimating using physics...that's great!

I also measure the size of my Burgundy Tablecloths. Hahaha...can't hardly made it.
 
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