Course: ME302-Mechanics of Materials Due date: 09/08/2015 Homework Assignment 1(Chap1-2)

1. A frame of formed by joining a bent beam ACD with a bar BC by a hinge is supported at A and B as shown in Fig.1. A vertical load P=150N is applied at point D. For each member, determine: (a) The components of support reactions at A and B (b) The axial force, shear force, and bending moment acting on the cross section at point O

Fig.1

2. Determine the average shear stress developed in pin A of the truss. A horizontal force of P=40kN is applied to joint C. Each pin has a diameter of 25mm and is subjected to double shear.

Fig.2

3. The built-up rod BC consisting of a solid bar AB of diameter dAB=1in. and a 2-in. nominal diameter standard steel tube (see the below table) is subjected to axial forces as shown in Fig.3. Calculate the normal stress in each part, AB and BC.

Fig.3

4. To the nearest 1/16 in., determine the required

thickness of member BC and the diameter of the pins at A and B if the allowable normal stress for member BC is = and the allowable shear stress for the pins is = .

5. The force applied at the handle of the rigid lever causes the lever to rotate clockwise about the pin B through at angle of 2o. Determine the average normal strain developed in each wire. The wires are unstretched when the lever is in the horizontal position.

6. The rectangular plate is deformed into the shape of a parallelogram shown by the dashed lines. Determine the average shear strain at corners A and B.