# Bending of beams

1. Dec 10, 2007

### wock

1. The problem statement, all variables and given/known data
3. Calculate the minimum diameter of drum on which copper strip 4mm thick may be wound if the maximum bending stress is not to exceed 332MN/m2.
Assume E = 95 GN/m2

σ /(yxE)=r

2. Relevant equations

3. The attempt at a solution

would this work if so i make it 1.7m aprox

Last edited: Dec 10, 2007
2. Dec 11, 2007

### FredGarvin

I believe you need to invert that answer. The form I am used to seeing is

$$\frac{1}{\rho}=\frac{\sigma_{max}}{E*c}$$

Where rho is the radius of curvature.