Recent content by tone999

Homework Statement A thick cylinder of 100mm internal radius and 150mm external radius is subjected to an internal pressure of 60MN/m^2 and an external pressure of 30MN/m^2. Determine the hoop and radial stresses at the inside and outside of the cylinder together with the longitudinal stress...

If that rod, with thermal expansion coefficient 6 x10^-6 is cooled by 20 OC, what is the resulting thermal strain? Is this just 6x10^-6/(20)(0.000182)=5.46x10^-11

Homework Statement A strip of elastomer was stretched in tension and elongation and was held constant. After 10 minutes the tensile stress in the specimen dropped by 12%. Assuming that the elastomer behaves in accordance with the maxwell model: (i) Calculate the relaxation time (to the...

Strain = 1kN / ((pi*1^2)/4 * 70GPa) = 1kN / (.7854cm^3 * 70GPa) Strain = 1000N / (785mm^2 * 70000 N/mm^2) = 0.000182 Is this correct now?

elastic modulus = stress/strain 70,000 = 0.01/1000 Answer in pascal units Is this anywhere near the correct method?

Homework Statement If a glass rod of diameter 1cm is loaded with a 1kN tensile load and has a young's modulus of 70 GPa, what is the tensile strain? Homework Equations The Attempt at a Solution Im sure if somebody could tell me the formula for this i could work it out easily

Homework Statement For a continuous fibre reinforced polymer, use a diagram to explain how the Young's modulus of the composite varies with fibre orientation and fibre content. Anywhere i could get any of this information? I've been googling with no success for a while

Homework Statement The amplitude of a torsional vibration decreases so that the amplitude on the 100th cycle is 13% of the the amplitude of the first cycle. Determine the level of damping in terms of the logarithmic decrement. Homework Equations The Attempt at a Solution Is this...

The amplitude of a torsional vibration decreases so that the amplitude on the 100th cycle is 13% of the the amplitude of the first cycle. Determine the level of damping in terms of the logarithmic decrement. Is this simply ln(100/13)= 2.04 or ln(13/100)= -2.04?

Homework Statement Describe how resonance in a domestic spin-dryer could be overcome? The Attempt at a Solution The internal unit of a washing machine or spin-dryer normally includes a washing container, which has a laundry drum mounted in the container such that it can rotate, and an...

Yeah I've got that. I mean "r" on its own in the equation. I know the values for r1 - 0.015m r2 - 0.025m Internal pressure - 60x10 to the power of 6 Nm2

Homework Statement A cylinder has an internal diameter of 30mm and an external diameter of 50mm and is subject to an internal pressure which is 60MPa above that in the air surrounding the cylinder. Determine the radial and hoop stresses at the inner and outer surfaces. Homework...

hi hi sorry i took so long 2 come back to this problem.yes the first equation is the one i am using. there's a few things i didnt understand firstly where do the divison parts come from eg (1/6) (1/2)? and maybe its just a typo but should the z be there: "(1/6)y^3y^3z" and instead a t^3...

another power series question... I tried it for awhile but it just got out of hand and the amount of numbers got unbearable. Q. The increase in resistance of strip conductors due to eddy currents at power frequencies is given by : X = yt divided by 2 (sinh yt + sin yt divided by cosh yt -...

Hi I've got 2 questions I am not to sure about. 1.Evaluate sinh(1.6), correct to 5 decimal places, using power series methods. I think i got the answer to this as being 3.16200 by using the series expansion for sinh "x" and putting 1.6 into the equation. 2.Determine the power series for...