## Bending Tensile Stress

In the below figure, a beam is loaded by hanging a 1,500 N downward force. What is the tensile stress due to bending?

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__
__**Hint**

**Hint**

Because there is a fixed roller towards the middle section of the beam, the max bending moment occurs on the beam's right portion:

$$$Max\:Bending\:Moment=force\times distance$$$

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__**Hint 2**

**Hint 2**

The normal stress in a beam due to bending:

$$$\sigma_x=\frac{My}{I}$$$

where
$$M$$
is the moment at the section,
$$I$$
is the moment of inertia of the cross section, and
$$y$$
is the distance from the neutral axis to the fiber location above or below the neutral axis.

Because there is a fixed roller towards the middle section of the beam, the max bending moment occurs on the beam's right portion:

$$$Max\:Bending\:Moment=force\times distance$$$

$$$=1500N\times 850mm=1.275\cdot 10^6\:N\cdot mm$$$

The normal stress in a beam due to bending:

$$$\sigma_x=\frac{My}{I}$$$

where
$$M$$
is the moment at the section,
$$I$$
is the moment of inertia of the cross section, and
$$y$$
is the distance from the neutral axis to the fiber location above or below the neutral axis.

$$$\sigma_{tension}=\frac{(1.275\cdot 10^6N\cdot mm)(15mm)}{11\cdot 10^4mm^4}=174\:MPa$$$

174 MPa