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I want to find the friction coefficient of various fabrics against human skin. I don't want to cut the material to a smaller size.

Would the following tilt test work?

  1. Get a rigid, square board. Likely the board with be 18 x 18 inches.
  2. Attach the fabric to the board.
  3. Flip the board upside down so the fabric is now on the underside of the board.
  4. Balance the board, material side down, on my hand.
  5. Conduct tilt test by tilting hand slowly until board begins to slide and record the angle.

Does the fact that the board is much larger than my hand matter to the results of the tilt test?

Alternatively, would the following pull test work?

  1. Get a rigid, square board. Likely the board with be 18 x 18 inches.
  2. Attach the fabric to the board.
  3. Flip the board upside down so the fabric is now on the underside of the board.
  4. Balance the board, material side down, on my hand. Also ensure the board is level.
  5. Pull on the board with a spring scale and record the results.

Does the fact that the board is much larger than my hand matter to the results of the pull test?

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What I think about this is following. I request others to correct me if I am wrong-

The normal reaction by the hand would be also due to weight of the board. This will increase the frictional force and so you have to keep track of the component of weight of board which is acting on your hand in your first experiment.

One more thing is that you must ensure that the friction between the board and fabric does not affect your experiment. You can ensure this by attaching the fabric properly to the board so that the board does not slip over fabric.

I don't thing size of board will matter from the experiment point of view and the only thing that should matter about the board is its weight.

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  • $\begingroup$ So as long as I account for the weight of the board and ensure that the fabric is firmly attached to the board, the size of the board relative to my hand shouldn't matter? $\endgroup$
    – user803952
    Jan 18, 2018 at 15:41
  • $\begingroup$ I don't think that size should matter but I'm not 100 per cent sure as the pressure thing and uniformity of hand is troubling me. Let's weight for other answers... $\endgroup$ Jan 19, 2018 at 1:41

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