HP 50G, Руководство пользователя

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necessary to plot the circle. It is suggest that we re-order the variables in the
sub-directory, so that the programs
@MOHRC
and
@PRNST
are the two first variables
in the soft-menu key labels. This can be accomplished by creating the list {
MOHRCIRCL PRNST } using:
J„ä
@MOHRC @PRNST
`
And then, ordering the list by using:
„°
@)@MEM@@ @)@DIR@@ @ORDER
.
After this call to the function ORDER is performed, press
J
. You will now see
that we have the programs MOHRCIRCL and PRNST being the first two
variables in the menu, as we expected.
A second example of Mohr’s circle calculations
Determine the principal stresses for the stress state defined by
σ
xx
= 12.5 kPa,
σ
yy
= -6.25 kPa, and
τ
xy
= - 5.0 kPa. Draw Mohr’s circle, and determine from
the figure the values of
σ
’
xx
,
σ
’
yy
, and
τ
’
xy
if the angle
φ
= 35
o
.
To determine the principal stresses use the program
@PRNST
, as follows:
J
@PRNST
Start program PRNST
12.5˜
Enter
σ
x = 12.5
6.25\˜
Enter
σ
y = -6.25
5
\`
Enter
τ
xy = -5, and finish data entry.
The result is:
To draw Mohr’s circle, use the program
@MOHRC
, as follows:
J
@MOHRC
Start program PRNST
12.5˜
Enter
σ
x = 12.5
6.25\˜
Enter
σ
y = -6.25
5
\`
Enter
τ
xy = -5, and finish data entry.
The result is: