Question 71. A tourist covers half of his journey by train at 60 km/h, half of the remainder by bus at 30 km/h and
the rest by cycle at 10 km/h. The average speed of the tourist in km/h during his entire journey is

Question 72. What will be the maximum sum of 44, 42, 40, ...... ?

Question 73. A flywheel connected to a punching machine has to supply energy of 400 Nm while running at a
mean angular speed of 20 rad/s. If the total fluctuation of speed is not to exceed ±2%, the mass
moment of inertia of the flywheel in kg-m2 is

Question 74. Two cutting tools are being compared for a machining operation. The tool life equations are: Carbide tool: VT1.6 = 3000 HSS tool: VT0.6 = 200 where V is the cutting speed in m/min and T is the tool life in min. The carbide tool will provide higher tool life if the cutting speed in m/min exceeds

Question 75. The function f(t) satisfies the differential equation d2f/dt2 + f = 0 and the auxiliary conditions, f(0) = 0, df/dt (0) = 4. The Laplace transform of f (t) is given by

Question 76. In water jet machining, the water jet is issued through a 0.3 mm diameter orifice at a pressure of
400 MPa. The density of water is 1000 kg/m3. The coefficient of discharge is 1.0. Neglecting all
losses during water jet formation through the orifice, the power of the water jet in kW is

Question 77. A linear programming problem is shown below.Maximize       3x + 7ySubject to      3x + 7y ≤ 10                       4x + 6y ≤ 8                       x, y ≥ 0It has

Question 78. In a CAD package, mirror image of a 2D point P(5,10) is to be obtained about a line which passes
through the origin and makes an angle of 45° counterclockwise with the X-axis. The coordinates of
the transformed point will be

Question 79. Steam enters an adiabatic turbine operating at steady state with an enthalpy of 3251.0 kJ/kg and leaves as a saturated mixture at 15 kPa with quality (dryness fraction) 0.9. The enthalpies of the saturated liquid and vapor at 15 kPa are hf = 225.94 kJ/kg and hg = 2598.3 kJ/kg respectively. The
mass flow rate of steam is 10 kg/s. Kinetic and potential energy changes are negligible. The power output of the turbine in MW is

Question 80. For an opaque surface, the absorptivity (α), transmissivity (t) and reflectivity (ρ) are related by
the equation: