24.05.2018 Views

integration

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

390 INTEGRAL CALCULUS<br />

in Fig. 38.33. (In Fig. 38.33(b), the circular<br />

area is removed.) ⎡<br />

⎣ I AA = 4224 cm 4 ⎤<br />

,<br />

I BB = 6718 cm 4 , ⎦<br />

I cc = 37300 cm 4<br />

Figure 38.31<br />

6. Calculate the radius of gyration of a rectangular<br />

door 2.0 m high by 1.5 m wide about a<br />

vertical axis through its hinge.<br />

[0.866 m]<br />

7. A circular door of a boiler is hinged so that<br />

it turns about a tangent. If its diameter is<br />

1.0 m, determine its second moment of area<br />

and radius of gyration about the hinge.<br />

[0.245 m 4 , 0.559 m]<br />

8. A circular cover, centre 0, has a radius of<br />

12.0 cm. A hole of radius 4.0 cm and centre<br />

X, where OX = 6.0 cm, is cut in the cover.<br />

Determine the second moment of area and<br />

the radius of gyration of the remainder about<br />

a diameter through 0 perpendicular to OX.<br />

[14280 cm 4 , 5.96 cm]<br />

Figure 38.33<br />

11. Find the second moment of area and radius<br />

of gyration about the axis XX for the beam<br />

section shown in Fig. 38.34. [<br />

1350 cm 4 ,<br />

]<br />

5.67 cm<br />

9. For the sections shown in Fig. 38.32, find<br />

the second moment of area and the radius of<br />

gyration about axis [ XX.<br />

(a) 12190 mm 4 ]<br />

,10.9mm<br />

(b) 549.5cm 4 ,4.18 cm<br />

Figure 38.34<br />

Figure 38.32<br />

10. Determine the second moments of areas<br />

about the given axes for the shapes shown

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!