BASIC MECHANICAL ENGINEERING


BASIC MECHANICAL ENGINEERING

B.TECH
SEM III, 2012-13
UTTARAKHAND TECH. UNIVERSITY (UTU)


Time: 3 hours
Total Marks : 100
Attempt any four questions:
  1. Draw stress-strain diagram for Aluminium and explain its important points.
  2. What do you understand by thermodynamic equilibrium?
  3. Discuss PMM2 with the help of neat sketches?
  4. Water boil at a temperature of 100oC and pressure of 100 kPa. What will be the pressure inside a cooker in case water boil at 123oC?
  5. A mercury manometer shows a gauge pressure of 100 mm of Hg. In case it is replaced by a water manometer, what gauge pressure in mm of water will be shown by it? Take g =10 m/s2.
  6. A mass of 1.5 kg of air is compressed in a quasi-static process from 1.1 bar to 10 bar according to law Pv1.25 = constant, where v is 1.2 kg/m3. Find the work involved in compression process.
Attempt any four questions:
  1. Explain the equivalence between the kelvin- Planck and Clausius statement of the second law of thermodynamics.
  2. Draw the triple point and critical point of water on PT diagram.
  3. A uniform ladder of length 5 m and weighing 20 N is placed against a smooth vertical wall with its lower end 4m away from the wall. If the ladder is just to slip position, determine the coefficient of friction the ladder and floor.
  4. Define refrigerator. Show that the cop of a heat pump is greater than the cop of refrigerator by unity.
  5. Determine unavailable energy if a heat engine is working between the temperature limit of 1000K and 300K. Heat delivered to engine is 1000 J and work output is 400J.
  6. Discuss method of sections for solving truss problems.
Attempt any two question:
  1. Derive the expression for air standard efficiency of Diesel cycle and mean effective pressure.
  2. Draw the S.F.D and B.M.D for a cantilever of length L and having uniformly varying load of zero at free end and w at fixed end.
  3. The principle stresses at a point across two perpendicular planes are 75 MPa (tensile). Find the normal and tangential stresses and the plane at 20o with the major principle plane.
Attempt any two questions:
  1. Derive the Torsion equation and stating its assumptions.
  2. A conical bar having cross-sectional area of A at base and length L is hanging on its base. Find the total elongation of the bar due to its own weight  Assume the density of bar material as P and Modulus of elasticity of bar material as E.
    B.Tech, UTTARAKHAND TECH. UNIVERSITY (UTU)
  3. A member LMNP is subjected to point load as shown in Figure. Calculate , force P necessary for equilibrium and total elongation of the bar. Take E=210 GN/m2.

Attempt any two question:
  1. In a steam power plant, the steam of 0.1 bar and 0.95 dry enters the condenser and leaves as saturated liquid at 0.1 bar and 45oC. Cooling water enters the condenser at 20oC and leaves at 35oC. Determine the mass flow rate of cooling water to the condenser.
  2. A solid circular shaft transmits 75 kW power at 200 rpm, Calculate the shaft diameter, If the twist in the shaft is not exceed 1o in 2 meter length and the shear strength is limited to 50 MN/m. Take G = 100 GN/m2
  3. A CI pipe of wall thickness 10 mm and outside diameter 120 mm carries water and is supported at a distance of 9 m. Calculate the value of maximum bending stress and its nature when water is running full. Take the density of water as lg/cc and for CI as 7 g/cc.
at
Labels: , , ,