06 Solutions 46060_Part1

5/27/10

3:51 PM

Page 329

© 2010 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist. No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher.

6–1. Draw the shear and moment diagrams for the shaft. The bearings at A and B exert only vertical reactions on the shaft.

A

B

250 mm

800 mm

24 kN

6–2. Draw the shear and moment diagrams for the simply supported beam.
M A 2m 2m 2 kN m

4 kN

B 2m

329

06 Solutions 46060_Part1

5/27/10

3:51 PM

Page 330

© 2010 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist. No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher.

6–3. The engine crane is used to support the engine, which has a weight of 1200 lb. Draw the shear and moment diagrams of the boom ABC when it is in the horizontal position shown. a + ©MA = 0; 4 F (3) - 1200(8) = 0; 5 A -Ay + Ax 4 (4000) - 1200 = 0; 5

A

3 ft B

5 ft C

FA = 4000 lb

4 ft

+ c ©Fy = 0; + ; ©Fx = 0;

Ay = 2000 lb

3 (4000) = 0; 5

Ax = 2400 lb

*6–4. Draw the shear and moment diagrams for the cantilever beam.

2 kN/m

A 2m

6 kN m

The free-body diagram of the beam’s right segment sectioned through an arbitrary point shown in Fig. a will be used to write the shear and moment equations of the beam. + c ©Fy = 0; V - 2(2 - x) = 0 V = {4 - 2x} kN‚ (1)

1 a + ©M = 0; -M - 2(2 - x)c (2 - x) d - 6 = 0 M = {-x2 + 4x - 10}kN # m‚(2) 2 The shear and moment diagrams shown in Figs. b and c are plotted using Eqs. (1) and (2), respectively. The value of the shear and moment at x = 0 is evaluated using Eqs. (1) and (2). V x = 0 = 4 - 2(0) = 4 kN M x = 0