1. Mechanical Engineering Statics 5th Edition Solution Manual Pdf Bedford
2. Mechanical Engineering Statics 5th Edition Solution Manual

Problem 2.1 In Active Example 2.1, suppose that the vectors U and V are reoriented as shown. The vector V is vertical. The magnitudes are jUj D 8 and jVj D 3. Graphically determine the magnitude of the vector U C 2V. 45⬚ U V Solution: Draw the vectors accurately and measure the resultant. R D jU C 2Vj D 5.7 R D 5.7 Problem 2.2 Suppose that the pylon in Example 2.2 is moved closer to the stadium so that the angle between the forces FAB and FAC is 50°. Draw a sketch of the new situation.

The magnitudes of the forces are jFAB j D 100 kN and jFAC j D 60 kN. Graphically determine the magnitude and direction of the sum of the forces exerted on the pylon by the cables. Solution: Accurately draw the vectors and measure the magnitude and direction of the resultant jFAB C FAC j D 146 kN ˛ D 32° c 2008 Pearson Education, Inc., Upper Saddle River, NJ.

Description Statics and Mechanics of Materials 5th Edition Solutions Manual Hibbeler This is completed downloadable package SOLUTIONS MANUAL for Statics and Mechanics of Materials 5th Edition by Russell C. Description Statics and Mechanics of Materials 5th Edition Solutions Manual Hibbeler This is completed downloadable package SOLUTIONS MANUAL for Statics and Mechanics of Materials 5th Edition by Russell C.

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. 7 Problem 2.3 The magnitude jFA j D 80 lb and the angle ˛ D 65°. The magnitude jFA C FB j D 120 lb. Graphically determine the magnitude of FB. FB FC ␤ a FA Solution: Accurately draw the vectors and measure the magnitude of FB.

JFB j D 62 lb Problem 2.4 The magnitudes jFA j D 40 N, jFB j D 50 N, and jFC j D 40 N. The angle ˛ D 50° and ˇ D 80°. Graphically determine the magnitude of FA C FB C FC. FB FC ␤ a FA Solution: Accurately draw the vectors and measure the magnitude of FA C FB C FC.

R D jFA C FB C FC j D 83 N 8 c 2008 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.

Problem 2.5 The magnitudes jFA j D jFB j D jFC j D 100 lb, and the angles ˛ D 30°. Graphically determine the value of the angle ˇ for which the magnitude jFA C FB C FC j is a minimum and the minimum value of jFA C FB C FC j.

FB FC ␤ a FA Solution: For a minimum, the vector FC must point back to the origin. R D jFA C FB C FC j D 93.2 lb ˇ D 165° Problem 2.6 The angle  D 50°.

Graphically determine the magnitude of the vector rAC. 150 mm 60 mm B rAB rBC ␪ A rAC C Solution: Draw the vectors accurately and then measure jrAC j. JrAC j D 181 mm c 2008 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. 9 Problem 2.7 The vectors FA and FB represent the forces exerted on the pulley by the belt. Their magnitudes are jFA j D 80 N and jFB j D 60 N. Graphically determine the magnitude of the total force the belt exerts on the pulley. Solution: Draw the vectors accurately and then measure jFA C FB j. JFA C FB j D 134 N FB 45⬚ FA 10⬚ Problem 2.8 The sum of the forces FA C FB C FC D 0.

The magnitude jFA j D 100 N and the angle ˛ D 60°. Graphically determine the magnitudes jFB j and jFC j. Solution: Draw the vectors so that they add to zero.

JFB j D 86.6 N, jFC j D 50.0 N FB 30 a FA FC Problem 2.9 The sum of the forces FA C FB C FC D 0. The magnitudes jFA j D 100 N and jFB j D 80 N. Graphically determine the magnitude jFC j and the angle ˛.

FB 30 a FA FC Solution: Draw the vectors so that they add to zero. JFC j D 50.4 N, ˛ D 52.5° 10 c 2008 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.

Problem 2.10 The forces acting on the sailplane are represented by three vectors. The lift L and drag D are perpendicular.

The magnitude of the weight W is 500 lb. The sum of the forces W C L C D D 0. Graphically determine the magnitudes of the lift and drag. L 25⬚ D W Solution: Draw the vectors so that they add to zero.

Then measure the unknown magnitudes. JLj D 453 lb jDj D 211 lb Problem 2.11 A spherical storage tank is suspended from cables. The tank is subjected to three forces, the forces FA and FB exerted by the cables and its weight W.

The weight of the tank is jWj D 600 lb. The vector sum of the forces acting on the tank equals zero.

Graphically determine the magnitudes of FA and FB. FA 40˚ Solution: Draw the vectors so that they add to zero. Then measure the unknown magnitudes. JFA j D jFB j D 319 lb FB 20˚ 20˚ W c 2008 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. 11 Problem 2.12 The rope ABC exerts forces FBA and FBC of equal magnitude on the block at B. The magnitude of the total force exerted on the block by the two forces is 200 lb.

Graphically determine jFBA j. Solution: Draw the vectors accurately and then measure the unknown magnitudes. JFBA j D 174 lb FBC C 20⬚ B B FBA A Problem 2.13 Two snowcats tow an emergency shelter to a new location near McMurdo Station, Antarctica. (The top view is shown. The cables are horizontal.) The total force FA C FB exerted on the shelter is in the direction parallel to the line L and its magnitude is 400 lb. Graphically determine the magnitudes of FA and FB.

Solution: Draw the vectors accurately and then measure the unknown magnitudes. JFA j D 203 lb jFB j D 311 lb L FA 30⬚ 50⬚ FB Top View Problem 2.14 A surveyor determines that the horizontal distance from A to B is 400 m and the horizontal distance from A to C is 600 m. Graphically determine the magnitude of the vector rBC and the angle ˛. North Solution: Draw the vectors accurately and then measure the unknown magnitude and angle. JrBC j D 390 m ˛ D 21.2° B a rBC C 60⬚ 20⬚ A 12 East c 2008 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.

Problem 2.15 The vector r extends from point A to the midpoint between points B and C. Prove that C r D 21 ⊲rAB C rAC ⊳. RAC r rAB B A Solution: The proof is straightforward: C r D rAB C rBM, and r D rAC C rCM. RAC r Add the two equations and note that rBM C rCM D 0, since the two vectors are equal and opposite in direction. Thus 2r D rAC C rAB, or r D
1 2 ⊲rAC C rAB ⊳ A M B rAB Problem 2.16 By drawing sketches of the vectors, explain why U C ⊲V C W⊳ D ⊲U C V⊳ C W.

Solution: Additive associativity for vectors is usually given as an axiom in the theory of vector algebra, and of course axioms are not subject to proof. However we can by sketches show that associativity for vector addition is intuitively reasonable: Given the three vectors to be added, (a) shows the addition first of V C W, and then the addition of U. The result is the vector U C ⊲V C W⊳. (b) shows the addition of U C V, and then the addition of W, leading to the result ⊲U C V⊳ C W.

V+W (a) W U+V+W V U U+V (b) W The final vector in the two sketches is the same vector, illustrating that associativity of vector addition is intuitively reasonable. Problem 2.17 A force F D 40 i  20 j ⊲N⊳. What is its magnitude jFj? V U U+V+W p Solution: jFj D 402 C 202 D 44.7 N Strategy: The magnitude of a vector in terms of its components is given by Eq. Problem 2.18 An engineer estimating the components of a force F D Fx i C Fy j acting on a bridge abutment has determined that Fx D 130 MN, jFj D 165 MN, and Fy is negative. Solution: jFj D  jFy j D jFx j2 C jFy j2  jFj2  jFx j2 D  ⊲165 MN⊳2  ⊲130 MN⊳2 D 101.6 MN Fy D 102 MN c 2008 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. 13 Problem 2.19 A support is subjected to a force F D Fx i C 80j (N). If the support will safely support a force of 100 N, what is the allowable range of values of the component Fx? Solution: Use the definition of magnitude in Eq.

Mechanical Engineering Statics 5th Edition Solution Manual Pdf Bedford

(2.8) and reduce algebraically. 100 ½  ⊲Fx ⊳2 C ⊲80⊳2, from which ⊲100⊳2  ⊲80⊳2 ½ ⊲Fx ⊳2. Thus jFx j  Problem 2.20 If FA D 600i  800j (kip) and FB D 200i  200j (kip), what is the magnitude of the force F D FA  2FB? Solution: Take the scalar multiple of FB, add the components of the two forces as in Eq. (2.9), and use the definition of the magnitude. F D ⊲600  2⊲200⊳⊳i C ⊲800  2⊲200⊳⊳j D 200i  400j jFj D Problem 2.21 The forces acting on the sailplane are its weight W D 500j⊲lb⊳, the drag D D 200i C 100j(lb) and the lift L. The sum of the forces W C L C D D 0.

Determine the components and the magnitude of L. P 3600, or 60  ⊲Fx ⊳  C60 (N)  ⊲200⊳2 C ⊲400⊳2 D 447.2 kip y L Solution: D L D W  D D ⊲500j⊳  ⊲200i C 100j⊳ D 200i C 400j⊲lb⊳ jLj D  ⊲200 lb⊳2 C ⊲400 lb⊳2 D 447 lb L D 200i C 400j⊲lb⊳, jLj D 447 lb 14 W x c 2008 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.

Problem 2.22 Two perpendicular vectors U and V lie in the x-y plane. The vector U D 6i  8j and jVj D 20. What are the components of V? (Notice that this problem has two answers.) Solution: The two possible values of V are shown in the sketch. Y The strategy is to (a) determine the unit vector associated with U, (b) express this vector in terms of an angle, (c) add š90° to this angle, (d) determine the two unit vectors perpendicular to U, and (e) calculate the components of the two possible values of V.

The unit vector parallel to U is eU D  6i 62 C ⊲8⊳2 8j  D 0.6i  0.8j 2 6 C ⊲8⊳2 V2 6 V1 U x 8 Expressed in terms of an angle, eU D i cos ˛  j sin ˛ D i cos⊲53.1° ⊳  j sin⊲53.1° ⊳ Add š90° to find the two unit vectors that are perpendicular to this unit vector: ep1 D i cos⊲143.1° ⊳  j sin⊲143.1° ⊳ D 0.8i  0.6j ep2 D i cos⊲36.9° ⊳  j sin⊲36.9° ⊳ D 0.8i C 0.6j Take the scalar multiple of these unit vectors to find the two vectors perpendicular to U. V1 D jVj⊲0.8i  0.6j⊳ D 16i  12j.

Mechanical Engineering Statics 5th Edition Solution Manual

The components are Vx D 16, Vy D 12 V2 D jVj⊲0.8i C 0.6j⊳ D 16i C 12j. The components are Vx D 16, Vy D 12 Problem 2.23 A fish exerts a 10-lb force on the line that is represented by the vector F. Express F in terms of components using the coordinate system shown. Solution: We can use similar triangles to determine the components of F. F D ⊲10 lb⊳ y   11 7 p i p j D ⊲5.37i  8.44j⊳ lb 72 C 112 72 C 112 F D ⊲5.37i  8.44j⊳ lb 7 11 F x c 2008 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 mate.