7. The velocity field of an incompressible flow in a Cartesian system is represented by V=2(x-y)i+vj+3k Which one of the following expressions for v is valid? (A) -4xy-4xz (B) -4xz+6xy (C) 4xz-6xy (D) 4xy + 4xz 8. A helical gear with 20 pressure angle and 30 helix angle mounted at the mid span of a shaft that is supported between two bearings at the ends. The nature of the stresses induced in the shaft is (A) normal stress due to bending in two planes; shear stress due to torsion (B) normal stress due to bending in two planes and axial loading; shear stress due to torsion (C) normal stress due to bending only (D) normal stress due to bending in one plane and axial loading; shear stress due to torsion 9. A flywheel is attached to an engine to keep its rotational speed between 100 rad/s and 110 rad/s. If the energy fluctuation in the flywheel between these two speeds is 1.05kJ then the moment of inertia of the flywheel is kg.m. (round off to 2 decimal places). 10. A four bar mechanism is shown below. Q 600mm S P 400 mm R 300 mm M For the mechanism to be crank-rocker mechanism, the length of the link PQ can be (A) 200 mm (B) 350 mm (C) 300 mm (D) 80 mm 11. For three vectors A = 2j3k, B = 2+k and = 3-j, where i, j and k are unit vectors along the axes of a right-handed rectangular/Cartesian coordinate system, the value of (A.(BC)+6) is 12. For an ideal gas, a constant pressure line and a constant volume line intersect at a point, in the Temperature (T) versus specific entropy (s) diagram, Cp is the specific heat at constant pressure and Cy is the specific heat at constant volume. The ratio of the slopes of the constant pressure and constant volume lines at the point of intersection is (A) (B) C-C Cp P - CV (D) Cv