Question

Please answer all parts of the questions and please try making them clear and easy to understand.

CONCEPTUAL QUESTIONS: (Total Points 10, 1 points each question) 1- A plate is supported by a bal-and-socket joint at A, a roller joint at B, and a cable at C. How many unknown support reactions are there in this problem? 300 N 400 N i m A) Four forces and two moments B) Six forces C) Five forces D) Four forces and one moment 2-The steel plate, with known weight and non-uniform thickness and density, is supported as shown. Of the three parameters CG, CM, and centroi d, which one is needed for determining the support reactions? Are all three parameters located at the same point? Alcenter of gravity, yes) B(center of gravity, no) C(centroid, yes) D)(centroid, no) 3- When determining the centroid of the area of the previous question, which type of differential area element requires the least computational work? A) Vertical B) Horizontal C) Polar D) Any one of the above. on the body about that axis prevents rotation of a body about an axis, then the support exertsa 6) if a support B) Force8oth A and & D None of the A) Couple moment 7) If a force of magnitude F can four different 2-0 and minimum torque values on the nut. (Max, Min): be applied in four different 2-0 confgurations (e.ar & Si select the cases resulting in the maximum Q R typicallyequations of equilibrium are applied at every joint using the method of joints, t B) Three Four D) Sx A) Two -o, when a particle is in equilibrium, which of the following equations All of the above. None of the above 10) How many unknown support reactions are there in this problem? 40 Ib/ft 30° 4 ft 3 f A) Two forces and two couple moments C) Three forces B) One force and two couple moments D) Three forces and one couple moment CONCEPTUAL QUESTIONS.( Total Pointvia, 1 point each be in terms of-. Di Any of the option or A) 2) Considering friction forces and the indicated motion of the belt, how are belt tensions T3 and T2 nelated 8) T1 12 T1 T2 3) A column is loaded with a horizontal 100 N force. At which section are the internalP loads the lowest? 100N A) P B) a c) R D) s 4) In mechanics, the force component V acting tangent to, or along the face of, the section is called the A) Axial force B) Shear force D) Bending moment C) Normal force 5) The is the point defining the geometric center of an object. A) Center of gravity B) Center of mass D) None of the options C) Centroid 4- A column is loaded with a horizontal 100 N force. At which section are the internal loads largest? A) P B) Q C) R D) S 100 N 5- A 100 lb box with a wide base is pulled by a force P and A,-0.4. Which force orientation requires the least force to begin sliding? A) P(A) P(A) 10010 P(B) P(C) B) P(B) C) P(C) 100 lb D) Can not be determined 6- To study problems concerned with the motion of matter under the influence of forces, Le, dynamics, it is necessary to locate a point called A) Center of gravity B) Center of mass C) Centroid D) None of the above 7- When using the method of joints, typicallyequations A) Two 8- In the method of sections, generaly a "cut" passes through no more thanmembers in of equilibrium are applied at every joint. B) Three C) For D Six which the forces are unknown. D) 4 c) 3 B) 2 A) 1 9- If a support prevents translation of a body, then the support exerts a A) Couple moment B) Force C) Both A and B. D) None of the above 104f r _ { silm, and F={ 10 k } N, the moment rxF equals {-ㄧ _1Nm: on the body

Answer 1

4) A)P

Because the moment will be greater at P point which is farthest from the pivot point

5)A)P(A)

Because for slipping of the block with minimum force , force must be applied horizontally. In P(B) and P(C) , the force is applied at an angle so the force vector will be divided into horizontal and vertical components.

6) A) Center of mass

7) A)Two

Because in order to say a system is in equilibrium, the sum of all horizontal and vertical force equation must be equal to Zero.

9)C) Both

10) A) 50i

Solution:- r x f = 5j x 10k = 50 (j x k) = 50 i