1
HW #1
Solutions (Fall 2011)
Assigned problems:
2.5, 2.10, 2.18, 2.19, 2.23
2.5
(Confirmed)
(a)
Locations
of
W
1
Locations
of
W
2
Load at B Load at C
M
A
Probability
E
1
E
2
E
3
–
–
0
0
0
0.15
×
0.2=0.03
–
B
500
0
5,000
0.045
X
–
C
0
500
10,000
0.075
X
X
B
–
200
0
2,000
0.05
X
X
B
B
700
0
7,000
0.075
X
X
X
B
C
200
500
12,000
0.125
X
C
–
0
200
4,000
0.12
X
C
B
500
200
9,000
0.18
X
X
C
C
0
700
14,000
0.30
X
or, sorted by
M
A
:
Locations
of
W
1
Locations
of
W
2
Load at B Load at C
M
A
Probability
E
1
E
2
E
3
–
–
0
0
0
0.03
B
–
200
0
2,000
0.05
X
X
C
–
0
200
4,000
0.12
X
–
B
500
0
5,000
0.045
X
B
B
700
0
7,000
0.075
X
X
X
C
B
500
200
9,000
0.18
X
X
–
C
0
500
10,000
0.075
X
X
B
C
200
500
12,000
0.125
X
C
C
0
700
14,000
0.30
X
(b)
E
1
and
E
2
are not mutually exclusive because these two events can occur together, for example, when
the weight
W
2
is applied at C,
M
A
is 10,000 ft-lb; hence both
E
1
and
E
2
will occur.