Search results

  1. I

    Centroid of an object in a fluid

    Hi friends just a quick question, does the centroid of an object change if it is submerged in a fluid and is on an incline? Or indeed does the centroid of an object ever change when in a fluid or inclined? Thanks! Claudius
  2. I

    U-tube manometer fluid mechanics

    Hi friends - I'm at a lost on this particular problem which reads: a manometer consists of a U-tube, 7mm internal diameter, with vertical limbs with an enlarged upper end of 44mm diameter. the left-hand limb and the bottom of the tube are filled with water and the top of the right hand limb...
  3. I

    Simple fluids pressure question

    Hello friends I am again in need of some asistance, The Question is as follows: The pressure head in a gas main at a point 120 m above sea level is equivalent to 180 mm of water. Assuming that the densities of air and gas remain constant and equal to 1.202 kg m^-3 and 0.561 kg m^-3...
  4. I

    Engineers bending equation

    Hello friends, a question about the engineers bending equation, M/I = E/R = (sigma)/y so take for example a beam with a rectangular cross section with depth 'b'. Will y then equal b/2 ? As y is measured from the neutral axis? Thank you in advance for your time, Claudius
  5. I

    Second moment of area: I

    Hello my friends, so I am once again confused :frown: Is the second moment of area a universal property of a beam i.e the beams cross section? So what i mean to say is - if i have a beam and it is curved with a rectangular cross section, and take this same beam and ensure it to be now straight...
  6. I

    Question on notation

    Hello friends, I have this problem it reads: A random variable X is defined to be the larger of the two values when two dice are thrown, or the value if the values are the same. Find the probability distribution for X. So I don't know how to state "X is defined to be the larger of the...
  7. I

    Hello friends,I have this problem I'm having difficulty

    Hello friends, I have this problem I'm having difficulty with, it reads - simplify the following expression ( ( x + 2 ) / (x^(2) - 2x) ) - ( (x) / (x^(2) - 4) ) it wants me to simplify it into ( 4(x + 1) ) / ( x(x - 2) ( x + 2) ) I can't get it to...
  8. I

    Simple logs question

    Hello friends, so i have this problem it reads: how many solutions does the following equation have Log_a(x+3) + Log_a(x-4) = Log_a(8) ok so first i put all the logs on one side of the equation and solve for x after using log laws, and i get x = 4 and x = -3, however plugging...
  9. I

    Confusing question

    Hello friends, I have this question which stumps me because i have no idea what its actually asking for :S - it reads: calculate the value of the first derivative of f(x) = x^(2) -3x - 1/x at x = 2. In which interval does it lie? (a) -x <= x < 0 (b) 0 <= x < 4 (c)...
  10. I

    Shape of graph polynomial to the fifth degree

    Hello my friends, I have this problem and would appreciate someones help: Determine all intervals where the following function is increasing or decreasing. F(x) = -x^(5)+(5/2)x^(4)+(40/3)x^(3)+5 Solution To determine if the function is increasing or decreasing we will need the...
  11. I

    Simple bending beams question

    Hello friends, so i have this problem: A beam under test has a measured radius of curvature of 300 m. The bending moment applied to it is 8 Nm. The second moment of area is 8000 mm4. Calculate the modulus of elasticity for the material. ok so using the engineers bending equation i have...
  12. I

    Simple torsion question

    Hiya friends, so i have a little problem, A shaft is made from tube 25 mm outer diameter and 20 mm inner diameter. The shear stress must not exceed 150 Mpa. Calculate the maximum torque that should be placed on it ok so we have T/J = tau/r so T = (tau/r)*J - this should give me my...
  13. I

    Simple stress, strain, elongation relationship question

    Howdy ya'll, a relatively simple question, A circular bar 20mm in diameter and 1m long is subjected to an axial load of 50kN. Determine: (i) The normal stress. (ii) The normal strain. (iii) The elongation. Assume the material is steel with an Elastic Modulus of 200GPa. ok so i...
  14. I

    Finding the Image of a function

    Hi all, is there a way that one goes about solving for the image of a function in a purely analytical sense without having to use any sort of graphing calculator? btw i'm abit confused about the concept of image - it seems it is not the range which is what i thought it was :S? can someone...
Top