41. Electron beam machining process is suitable for the following type of material
(a) low melting point and high thermal conductivity
(b) low melting point and low thermal conductivity
(c) high melting point and low thermal conductivity
(d) high melting point and high thermal conductivity
42. The length of a second's pendulum is
(a) 90.0 cms (b) 100 cm
(c) 101 cm (d) 99.4 cm
43. The period of oscillation of a simple pendulum depends on
(a) mass of bob (b) its effective length
(c) radius of bob (d) density of bob
44. A spherical vessel with an inside diameter of 2 m is made of material having an allowable stress in tension of 500 kg/cm^2 The thickness of a shell to withstand a pressure of 50 kg/cm^2 should be
(a) 5 cm (b) 2.5 cm
(c) 10 cm (d) 1.25 cm
45. For best hydraulic rectangular cross section of an open channel, its depth should be equal to
(a) width/2 (b) 2*width
(c) width (d) $sqrt{width}
46. Compare the strength of solid and hollow shafts both having outside diameter D and hollow shaft having inside diameter of D/2 in torsion. The ratio of strength of solid to hollow shaft in torsion will be
(a) 0.5 (b) 15/16
(c) 0.75 (d) 0.25
47. Following gases are used in Tungsten gas welding
(a) hydrogen and Oxygen (b) Argon and Helium
(c) Argon and Neon (d) Helium and Neon
48. A heat engine is supplied heat at the rate of 30,000 J/s and gives an output of 9 kW. The thermal efficiency of engine will be
(a) 40% (b) 33%
(c) 30% (d) 50%
49. If a body is transmitting torque T kgm at angular speed of θ rad/s, then h.p. transmitted will be
(a) Tθ/75 (b) T/θ
(c) Tθ/50 (d) Tθ
50. The critical radius of insulation for a spherical shell is
(a) $\frac{thermal-conductivity-of-insulating-material}{heat-transfer-coefficient at outer surface}$
(b) inverse of (a)
(c) 2x $\frac{thermal-conductivity-of-insulating-material}{heat-transfer-coefficient at outer surface}$
(d) inverse of (c)
51. When a body slides down a surface inclined θ to horizontal, the acceleration (f) of the body is given by
(a) f =g (b) f = g cosθ
(c) f = g tanθ (d) f = g sinθ
52. If σ1 and σ2 be the major and minor stresses, then maximum value of tangential stress is equal to
(a) σ2 (b) σ1 - σ2
(c) σ1 + σ2 (d) ( σ1 - σ2)/2
53. The pressure in the air space above an oil (sp. Gravity 0.7) surface in a tank is 0.1 kg/cm^2. The pressure at 5 m below the oil surface will be
(a) 5 meters of water column
(b) 4 meters of water column
(c) 3.5 meters of water column
(d) 4.5 meters of water column
54. Thermal welding is a form of
(a) resistance welding
(b) gas welding
(c) fusion welding
(d) forge welding
55. The ratio of heat flow Q1/Q2 from two walls of same thickness having their thermal conductivities as K1 = 2*K2 will be
(a) 1 (b) 0.5
(c) 0.25 (d) 2
56.A Carnot engine has an efficiency of 0.5. The COP of refrigerant working with the same temperature limit is
(a) 0.5 (b) 1
(c) 2 (d) 1.25
57. Slack represents the difference between the
(a) latest allowable time and normal expected time
(b) latest allowable time and earliest expected time
(c) proposed allowable time and earliest expected time
(d) normal allowable time and latest expected time
58. A refrigerator operates on a reversed Carnot cycle between 900 and 300 K. If heat at the rate of 3 kJ/s is extracted from the low temperature space, then the power required to drive the refrigerator
(a) 3 kW (b) 6 kW
(c) 9 kW (d) 4 kW
59. If V is the mean velocity of the flow, then according to Darcy-Weisbach equation for pipe flow energy loss over a length of pipeline is proportional to
(a) V (b) 1/V
(c) 1/V^2 (d) V^2
60. 40% of the incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is
(a) 0.40 (b) 0.55
(c) 0.45 (d) 0.75
guys do check 48 and 59 no. question
ReplyDeleteThere was a typo mistake now corrected. Thanks for pointing it out.
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