Page 58 - eEISBN FINALIZE

MA = MA

6 =
2 +
4 +
20 ( ) 30 ( ) 40 ( ) G y ( )
12
40 + 120 + 240 = 12 G y
12 G y = 400
400
G =
y
12
= 33 . 33 kN

 F =  F 
A + G = 20 + 30 + 40
y
y
A + G y = 90
y
A y = 90 - G y

= 90 - 33.33

= 56 . 67 kN

→ 
 F =  F x
x
0 = A x
 A x = 0

MD = MD
6 =
3 +
2 +
F KJ ( ) 56 . 67 ( ) 30 ( ) 20 ( ) 4
F 3 KJ + 340 . 02 = 80 + 60
F 3 KJ + 340 . 02 = 140
3F = 140 − 340 . 02
KJ
− 200 . 02
F =
KJ
3
= -66.67kN (C)

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