Page 44 - 4749

Figure 2.12

is presented in the fig.2.12, b by shaded area. Then the total work
is done by a force P equals to the area  OAB
Р
  U  , (2.33)
2
where U – the potential energy of deformation. Substituting
equation (2.11) into (2.33), we obtain:
2
Р l
U  0 . (2.34)
2ЕA
To estimate the energy intensity of rod material define specific
potential energy accumulated per unit volume.
2
U P l 1  2
u   0   x , (2.35)
п
V 2EA Al 2E
0
or
1
u    , (2.36)
п x x
2
where V – the rod volume.

44