Post on 06-Jan-2016
description
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30N
4250
10N 10N
1.
20.1
22.3
38.6
46.0
TRANSLATIONAL:
Need :45.9 up
16.3 right
45.9
16.3
48.7 N @ 70°
ROTATIONAL:
10(7) = 70 CCW
20.1(5)= 101 CW
10(3.5)= 35 CCW
46(2) = 92 CW
NET = 88 Nm CW
48.7 N
70°
Where to put it:
= F d
88 = 45.9 dOnly the part causes torque!
1.91 m = dYou need CCW….so think if it should be 1.91 meters to left or right!
Need : 88 Nm CCW
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700 N
78
55
2. All angles of a triangle add to 180
47
55
55
800
T?
CW = CCW sin55(800)(2.5)+ sin55(700)(5) = sin47(T)(5)
1638 + 2867 = 3.657 T
1230 N = T
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3.
3050 65
Break the forces into components
11
19.1
7.71
9.19
18.1
8.45
TRANSLATIONAL: ROTATIONAL: Where to put it:
Need : 16.3 down
2.94 left
16.6 N @ 80
2.94
16.3
11(2) = 22.0 CCW
9.19(.5) = 4.6 CW
18.1(2) = 36.2 CCW
NET = 53.6 Nm CCW
Need: 53.6 Nm CW
= F d
53.6 = 16.3 d
3.29 m = d
Only the part causes torque!
You need CW….so think if it should be 3.29 meters to left or right!
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20.TA TB
205675
Put pivot pt on one of the
forces you don’t know(either one)
ROTATIONAL:
CW = CCW
205(1.5) + 675(2) = TB(3)
307.5 + 1350 = 3TB
553 N = TB
You could move pivot pt to other end to get TB
..or use TRANS like I did
TRANSLATIONAL:
UP = DOWN
TA + 553 = 205 + 675
TA = 327 N
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21.
196
T30°
ROTATIONAL:
CW = CCW
196 L = sin30 T L
T = 392 N
TRANSLATIONAL:
Up & Down already cancel
Need: cos30(392) to right
339 N to right
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22.
2000
T
1200
Tension is a right angle25
25
25
ROTATIONAL:
CW = CCW
sin25(2000)L + sin25(1200)(½ L) = T(¾ L)
845 + 254 = .75T
1465 N = T
TRANSLATIONAL:
619
1327
Break tension into Components to look at
forces UP, DOWN, LEFT, & RIGHT
Need: 1327 right 2581 up
2000 + 1200 - 6191327
2581
2902 N @ 63