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Mechanical Engineering

Rigid Bodies and Newton's Second Law of Motion

The wheel and axle system shown attached in Figure Q2 supports a free hanging mass of 360g. The mass is initially a distance of 2.16m above the floor level when it is released causing the mass to hit the floor 6.2s later. The mass of the wheel and axle system is 40.2kg and its effective radius of gyration is equal to 2.8cm. (

Problems of Velocity, Angular Velocity and Acceleration in Trains and Wheels

Question 1: A train accelerates uniformly along a straight track and passes three trackside markers. The distance between the first two markers is equal to 0.25 km and between the second and third the distance is 0.4km. The train takes 26.6 seconds to travel between the first two markers and its speed as it passes the second ma

Force Required to Punch a Hole into an Aluminium Sheet

Question 4: (a) Calculate the force required to punch out a rectangular hole 100m x 50mm in a 2mm thick aluminium sheet. The ultimate strength in shear is 125 MN/m^2. (b) If the maximum force which can be exerted by the press is 45kN, what is the greatest thickness that can be punched out? Question 5: Two co-axial sha

Effect of Direct and Shear Forces on a Steel Specimen

Question 1: The attached load/extension values were found when a steel specimen was tested to destruction. Calculate: 1. The stress at the limit of proportionality 2. The yield stress 3. The ultimate tensile stress (UTS) 4. Young Modulus of Elasticity 5. Percentage Reduction in area 6. The percentage elongation 7.

Analyze the Planner Equilibrium

The roof truss shown attached is roller and pin-joint supported at the right-hand and left-hand ends respectively and carries loads of 10kN, 8kN and 12 kN as shown. Show that the structure is stable and determine, using the method of resolution of forces at the joints, the magnitude and nature of the forces acting in each of


5. Determine the fraction of the radiation leaving the base of the cylindrical enclosure shown attached that escapes through a coaxial ring opening at its top surface. The radius and the length of the enclosure are r_1 = 10cm and L = 10cm, while the inner and outer radii of the ring are r_2 = 5 cm and r_3 = 8cm, respectively.

Weld analysis

Two steel plates are joined with a butt weld using a weld throat h of 3/8 in. and the length of weld 1 of 4in. How do I determine the shear stress in the weld for a shearing force of 15000 lbf?

Midrange and amplitude components

A shaft is subjected to a completely reversed bending stress such that Xmax=40kpsi and Xmin=-40kpsi. How do I determine the midrange component and the amplitude component? (X=sigma)

Endurance limit

A steel rod AISI 1018 has the rotating bending specimen's endurance limit of 32.2kpsi. How do I determine the endurance limit for the part if the Marin modifying factors are: ka=0.887, kb=1, kc=0.889, kd=ke, kf=1?

Endurance limit

A steel rod AISI 1040 has the ultimate tensile strength (Sut) of 113kpsi. How do I determine the rotating bending specimen's endurance limit at 10^6 cycles?

Principal stresses

The state of plane stress at a point in a member is zx=-20MPa, zy=90MPa, txy=60MPa. How do I find the principal stresses zx and zy?

Modulus of Elasticity

A linear isotropic material has the shear modulus of elasticity G of 11.5*10^6 psi and the Poisson's constant v of 0.3. How do I determine the Young's modulus of elasticity E?

Tensile stress

A 3.14insq. cross sectional area steel tension rod carries a load of 3140lbf. How do I calculate the tensile stress in the rod?

Analyze Planner Equilibrium

The structure shown in Figure Q. 1 (see attached) is a pin-jointed section of a canopy and carries a single load of 4 kN acting at the lower right-hand joint. Show that the section is stable and, determine the following: (a) The directions of the support reactions by locating the point of concurrency for the external force

Engineering statistics

(a) From the following table of durabilities of marine coatings on electrical boxes, find the following quantities: Durability (ASTM Salt Spray Test) Class Frequency Hours Midpoint Class Interval xi fi 100-103.9 102 6 104-107.9 106 12 108-111.9 110 18 112-115.9 114 28 116-119.9 118 14 120-123.9

Maximum stress

Find the maximum value of S>0 if a stress of... is applied to a 60 deg boron/epoxy lamina. Apply Maximum Stress failure, Tsai-Hill failure and Tsai-Wu failure theories.

Internal pressure

2. The control of pulling force is of critical importance to pultrusion process. What are the major force components in different process stages? And how would they respond to the change of resin viscosity, pulling speed, temperature, coefficient of thermal expansion of composite mixture, degree of shrinking, and coefficient of

Hoop stress

1. A pressure vessel is made of a cylindrical composite part produced by filament winding. Hoop winding is used in which the number of winding layer is 5 and the wall thickness for each layer is 1mm. The diameter of the vessel is 0.5m. The fiber material is known to be S-glass with a tensile strength of 4.5GPa, and the matrix m

Reaction forces

A horizontal beam under load can roll along a vertical guide as shown. What are the reaction loads at A? Shear? Axial?

Method of Joints

A truss is loaded as shown. How do I find the magnitude of the force in members DB and BF? Can it be done without the equations of equilibrium?

Shear diagrams

A beam is under applied loads shown. How can I describe the shear diagram for sections I through III?


Are the weights of members usually included in the analysis of truss structures?

Body in Equilibrium

When a body is in equilibrium, are the magnitudes of the unknown forces or moments independent of where they are located on the structure?

Longitudinal versus Transverse Vibrations in a bar

A 48 inch long by 2 inch diameter round steel rod (E=30e6 psi, density=0.28 lb/in3) is fixed at one end and free at the other. If the rod is struck transversely so that there is both a longitudinal and transverse wave generated, how long does it take for each wave to complete a cycle? If you wanted to record 5 cycles for each

Single degree of freedom vibration problems with forcing functions

Need help with this Undergraduate problem where two dampers are in series. For a vertical spring/damper system with mass (M) and a harmonic forcing function, Fmax Cos [omega x t] , two dampers are in series with coefficients, C1 and C2, and a single spring with constant, k. Determine the amplitude of the steady-state disp

Angular Velocity: Slender Bar, Stepped Disk and Slender Rods

Please see the attachment for proper formatting and diagrams. 1. The slender bar with a mass of 4 kg is released from rest at an angle of 35 degrees. What is the angular velocity of the bar when it is vertical? a. 0.667 rad/s b. 1.06 rad/s c. 0.888 rad/s d. 1.74 rad/s e. 2.31 rad/s 2. The stepped disk

Manufacturing processes factors

1. Explain the factors involved in selecting the appropriate type of abrasive for a particular grinding operation. 2. What are the consequences of allowing the temperatures to rise during grinding? (Q. 25.38). 3. What are the implications of using a smaller abrasive grain size (higher grit number) in a bonded grinding wheel?

Moment of Inertia Problems

The three problems attached having to do with moment of inertia of things like a yo-yo. I need help setting them up. Please send explanations with the answer so I can see how your answer was achieved.

Mass of Inertia and Angular Acceleration

1. Two slender rods are welded together at right angles and released from rest as shown. The two welded bars rotate freely around point C. Each bar is 10 lbs and is 1.5 ft long. At release, what is the acceleration magnitude of point B? 2. A vertical 0.2-meter-long slender bar with a uniform cross section is released from res