Reporte de resistencia de materiales

9.-
2klb w=1.8klb/Pie 2klb 4´´
6´´ 6´´

1´´
2´ 8´ 2´

ƩMA=0
(4klb)-14.4klb (4´)-RB(8´)-2klb=0
ƩMA= (-4klb)+(14.4)(4´)-RB(8´)+20klb=0
RB= 4-57.6-(20)8=9.208klb

10.- 6plg4plg
8plg
1plg Ȳ=Ʃ Y.AA= 288plg72plg=4in

Y | A | Y.A |
4plg | 48plg | 192plg |
4plg | 24plg | 96plg |
| 72plg | 288plg |

I=bh312=..251.75312=2044.27

FIG | Y | A | Y*A |1 | 0.125plg | 0.4375plg2 | 0.0546875plg3 |
2 | 1.125plg | 0.4375plg2 | 0.4921875plg3 |
| | 0.875plg2 | =0.546875plg3 |
11.-
FIG | I | A | d2 | A*d2 |
1 | 0.002278645| 0.4375plg2 | .52 | 0.109375plg4 |
2 | 0.111653645 | 0.4375plg2 | .52 | 0.109375plg4 |
| =0.11393229 | | | =0.21875plg4 |
γ=ΣY*AA=0.5468750.875=0.625plg
FIG1.I=B*H312=0.002278645
FIG2 I=B*H312=0.111653645
It=0.11393229+0.21875=0.33268229plg4



12.-
40mm
5mm

50mm
5mm
5mm

20mm

FIG | Y | A | Y*A |
1 | 2.5mm | 100mm2 |250mm3 |
2 | 30mm | 250mm2 | 7500mm3 |
3 | 57.5mm | 200mm2 | 11500mm3 |
| | =550mm2 | =19250mm3 |
Υ=ΣY*AΣI=19250550=35mm
FIG | I | A | d2 | A*d2 |
1 | 208.33 | 100mm2 |32.52 | 1056.25mm4 |
2 | 52083.33 | 250mm2 | 52 | 25mm4 |
3 | 416.66 | 200mm2 | 22.52 | 506.25mm4 |
| =52708.32mm | | | =1587.5mm4 |
FIG1. I=b*h312=208.33mm
FIG2.I=b*h312=52083.33mm
FIG3. I=b*h312=416.66mm

It=52708.32mm+1587.5mm4=54295.82mm

13.-

Υ=ΣY*AΣA=15000009375=160
FIG | Y | A | Y*A |
1 | 100mm | 4375mm2 | 437500mm3 |
2 |212.5mm | 5000mm2 | 1062500mm3 |
| | =9375mm2 | =1500000mm3 |

FIG1. I=b*h312=25*200312=16666666.67mm
FIG2. I=b*h312=175*25312=227864.5833mm
FIG | Y | A | d2 | A*d2 |
1 |16666666.67mm | 4375mm2 | 602 | 15750000mm3 |
2 | 227864.5833mm | 5000mm2 | 520.52 | 13781250mm3 |
| =16894531.25 | | | =29531250mm3 |


17.-
720(.6m) - RB(1m) – 720(1.6) =...