# Tensile Strength Question

## Homework Statement

In the course of the above research, they discovered that this spider silk has an ultimate strength #or
tensile strength of 1850mPa (see 11.4 in University Physics). Tensile stress is a measure of the
pressure in an object when it is stretched. Tensile strength is the maximum tensile stress that the
object can endure before breaking. The equation for tensile stress is Tensile Stress=F/A

where is the applied force F and A is the cross-sectional area of the object (in this case, the circle
formed by a cross-section of a fibre).

Ok, phew, so on to the question...

If Spiderman has mass 63.2kg , what is the minimum diameter of fibre (of C. darwini spider silk) required to support his weight?

## Homework Equations

Tensile strength=F/A

## The Attempt at a Solution

I know that the area of a circle is 2Pi*r^2 but when I plug everything in I always get the wrong answer. I used force as mg, which didn't work. Could anyone please help?
I usually end up with 0.412m.
THE QUESTION IS ASKED FOR IN METERS
thanks alot.

SteamKing
Staff Emeritus