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1. Eight kilometers below the surface of the ocean the pressure is 82Mpa. Determine the density of the seawater at this depth if the density at the surface is 1025kg/m3 and the average bulk modulus of elasticity is 2.3GPa.
a mixture of liquid water and vapour at 0.4 mpa with 13 percent quality is contained in a piston cylinder device. the mixture is then heated until the temparature is 200 degress Celcius, while the pressure remains constant, assume the process is reversible
a) Represent the process on a P-V diagram with respect to the saturation lines
b) determine the work done , the heat transferred and the internal energy change during the process
An artery with dimensions OD = 20 mm and ID = 17 mm is subjected to pressures ranging from 80 mmHg to 130 mmHg. (a) Determine the diameter of the artery of the systolic (highest) and diastolic (lowest) points. The material in the artery follows the relationship σ = kε 2 , with k = 25 MPa. (b) Plot the pressure–radius curve due to the internal pressure from the stress–strain response of the material.
What is the distribution of stresses in an artery that has internal stresses such that (a) α = 180°; (b) α = 150°?At what internal pressure will the stress outside and inside the wall become the same? Assume (i) that the stress from the pressure decays linearly to zero at the external surface, and (ii) a linear elastic behavior with E = 400 MPa. Given: ID = 15 mm; OD = 22 mm.
Stress shielding is a serious problem in some implants since bone remodels and the decrease of stress leads invariably to the weakening of the bone. Calculate the stresses in the femur head bone with and without an implant. Consider three cases: titanium implant,
E = 113 GPa; stainless steel implant,
E = 205 GPa;
carbon–polymer (polysulfone–PEEK) composite implant, E = 30 GPa. Given: outer diameter of femur = 3 cm; inner diameter = 1.5 cm; Eb = 20 GPa.
Calculate the maximum strength for the following two cases, using the Griffith equation. Given: (i) mineral platelets have thickness of 1 mm and diameter of 10 nm;
(ii) mineral platelets have thickness of 1 nm and diameter of 50 nm.
Assume γsurf = 1 J/m2 ; EHAP = 100 GPa.
Leonardo’s airplane had a wing span of approximately 7 m; the wings had a width of approximately 2 m. The rule of thumb for birds and other low-velocity flying machines is 5 kg/m2 . Would Leonardo’s plane glide?
An artery with dimensions OD = 20 mm and ID = 17 mm is subjected to pressures ranging from 80 mmHg to 130 mmHg.
(a) Determine the diameter of the artery of the systolic (highest) and diastolic (lowest) points. The material in the artery follows the relationship σ = kε 2 , with k = 25 MPa.
(b) Plot the pressure–radius curve due to the internal pressure from the stress–strain response of the material.
The diameters of the plunger and ram are 50 mm and 0.5 m respectively.
The ram is 1.75 m below the plunger and the mass density of the liquid
in the hydraulic press is 820 kg/m3. The mass of the plunger and the ram
are 6 kg and 400 kg respectively. The plunger is forced vertically down
by a lever with a mechanical advantage of 6 to 1 onto which a force of
800 N is applied. The ram moves upwards when the plunger moves
downwards. Determine the maximum lifting force exerted by the ram.
Calculate the moment of inertia, Izz, of the simple crankshaft in the figure below. The material has a density of 7700kg/m3. All the round parts have a diamter of 50mm. All diamtions is in millimeters. Both ends are 60mm in length.
