How to Calculate a Shear Stress
- 1). Measure the area of the side of the object that is in contact with the object applying force in meters. For example, if your objects are two boxes sliding past one another, measure the area of the side of the box. To find the area, measure the length and width of the side of the object with your ruler and then multiply these two values together.This will be your "A" in the shear stress equation.
- 2). Find the force applied to the object by using your newton meter. Newton meters are used to determine forces in newtons. The newton meter is a specifically calibrated spring in a cylindrical container with a hook on the free end of the spring. Affix your newton meter to your sliding object with the hook. Determine the force by reading the scale of your newton meter. This number will be your "F" in the shear stress equation.
- 3). Plug your F and A values into the shear stress equation: tau = F/A. Use your calculator to divide F by A. The resulting number will be your shear stress value in pascals.
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