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b)

Figure 7.2

We see that the magnitude of the longitudinal force varies
according to a parabolic law and reaches a maximum value on the
axis of rotation
F 2 l 2
N max  . (7.7)
2
The same happens when cross section maximum tensile
stress is normal to the forces of inertia
 2 l 2
  . (7.8)
max
2

7.2 Calculation under shock loads

Blow is called the load transmitted over the body for small
amount of time and causes it significant acceleration, and hence
large inertial forces. Taking into account the nature of the
application of force to the rod we can distinguish longitudinal,
transverse and twisting strokes.

7.2.1 Technical theory of shock

Determination of particle acceleration at impact material
is problematic. Therefore, to solve problems typically use the law
of conservation of energy. At the same time build a simplified
calculation model system based on a set of assumptions that
usually provide sufficient accuracy for engineering calculations.

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