Monday, October 15, 2018

newtonian mechanics - Knots and strengh of a rope



I read a few times that a knot can reduce the strenght of a rope, but I can't understand why this happens. Can someone explain me what happens to a rope tied with a generic knot and stretched? Is there a way to calculate the reduction of resistance from the form of the knot?



Answer



A knot always requires the rope in the knot to be curved. This increases the stress on the outside of the curved bit of rope, and decreases the stress in the inside. This increase in the stress in a knot means the rope breaks at a lower overall stress than a straight rope would.



No comments:

Post a Comment

classical mechanics - Moment of a force about a given axis (Torque) - Scalar or vectorial?

I am studying Statics and saw that: The moment of a force about a given axis (or Torque) is defined by the equation: $M_X = (\vec r \times \...