Question

57. BIO While browsing books on neurophysiology, you come across a book published in 1967 by Soviet neurophysiologist Nikolai Aleksan- drovich Bernstein, The Co-ordination and Regulation of Movements, in which he describes a technique to determine the mass of a part of the human body if the position of the center of mass of that body part is known. His technique for determining the mass of the forearm is described as fol- lows: The person lies on a support board, as shown in Figure P8.57. Two readings of the scale are taken: first with the forearm held in position 1 (m) and second with it in position 2 (m2). Knowing the distance from the elbow to the center of mass of the forearm (d) and the distance between the knife edges supporting the board (D), the mass of the forearm and hand can be 62 R Bl ter via bo TI calculated from the following expression: Or is to D(m2-m) mh to (a) First, without deriving the expression, evaluate it to see if it is reasona- ble. Are the units correct? Is the sign of the expression positive? Are quali- tative dependences reasonable? (b) Now derive the expression. (c) Why do you think it is important to place the support board on knife edges instead of rigid blocks? FIGURE P8.57 Scale Position 2 Position 1 D

Answer 1

Answer of the given question is attached in the image format, please find the attachment.
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