The relation governing the simple bending of beam is:
1
\(\frac{\sigma}{y} = \frac{M}{E} = \frac{R}{I}\)
2
\(\frac{\sigma}{y} = \frac{M}{E} = \frac{E}{I}\)
3
\(\frac{\sigma}{E} = \frac{I}{M} = \frac{y}{R}\)
4
\(\frac{\sigma}{y} = \frac{M}{I} = \frac{E}{R}\)