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Translational & Rotational Homework. 1. ANSWER: 48.7 N @ 70 1.91 m to right of pivot pt. GOT IT!. Show me. 30N. Where to put it:. ROTATIONAL:. 42 . 50 . 10N. 10N. 1. 48.7 N. 20.1 22.3. 38.6 46.0. 70 °. TRANSLATIONAL:.
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Translational & Rotational Homework
1. ANSWER: 48.7 N @ 70 1.91 m to right of pivot pt GOT IT! Show me
30N Where to put it: ROTATIONAL: 42 50 10N 10N 1. 48.7 N 20.1 22.3 38.6 46.0 70° TRANSLATIONAL: Need : 45.9 up 16.3 right = F d 10(7) = 70 CCW 20.1(5) = 101 CW 10(3.5) = 35 CCW 46(2) = 92 CW NET = 88 Nm CW 88 = 45.9 d Only the part causes torque! 1.91 m = d 48.7 N @ 70° 45.9 16.3 You need CCW….so think if it should be 1.91 meters to left or right! Need : 88 Nm CCW
2. ANSWER: 1230 N GOT IT! Show me
All angles of a triangle add to 180 78 55 700 N 2. T? 47 55 55 800 CW = CCW sin55(800)(2.5)+ sin55(700)(5) = sin47(T)(5) 1638 + 2867 = 3.657 T 1230 N = T
3. ANSWER: 16.6 N @ 80 3.29 m to right of pivot pt GOT IT! Show me
ROTATIONAL: Where to put it: 3. Break the forces into components 18.1 9.19 19.1 65 50 30 7.71 8.45 11 TRANSLATIONAL: = F d Need : 16.3 down 2.94 left 11(2) = 22.0 CCW 9.19(.5) = 4.6 CW 18.1(2) = 36.2 CCW NET = 53.6 Nm CCW 53.6 = 16.3 d 2.94 Only the part causes torque! 3.29 m = d 16.3 You need CW….so think if it should be 3.29 meters to left or right! 16.6 N @ 80 Need: 53.6 Nm CW
20. ANSWER: 553 N & 327 N GOT IT! Show me
ROTATIONAL: 20. TA TB Put pivot pt on one of the forces you don’t know (either one) You could move pivot pt to other end to get TB ..or use TRANS like I did 205 675 TRANSLATIONAL: CW = CCW UP = DOWN 205(1.5) + 675(2) = TB(3) TA + 553 = 205 + 675 307.5 + 1350 = 3TB TA = 327 N 553 N = TB
21. ANSWER: T = 392 N 0 vertical & 339 N horizontal to right GOT IT! Show me
T 196 21. 30° ROTATIONAL: TRANSLATIONAL: CW = CCW Up & Down already cancel 196 L = sin30 T L Need: cos30(392) to right T = 392 N 339 N to right
22. ANSWER: T = 1465 n “Reaction Force” 2902 N @ 63 GOT IT! Show me
22. 619 T Tension is a right angle Break tension into Components to look at forces UP, DOWN, LEFT, & RIGHT 25 25 1327 2000 25 1200 TRANSLATIONAL: ROTATIONAL: CW = CCW Need: 1327 right 2581 up 2581 sin25(2000)L + sin25(1200)(½ L) = T(¾ L) 845 + 254 = .75T 2000 + 1200 - 619 1327 1465 N = T 2902 N @ 63