81. The moment of inertia of a solid cone of mass ‘m’ and base radius ‘r’ about its vertical axis is

• 3mr²/5
• 3mr²/10
• 2mr²/5
• 4mr²/5

Solution

• Sannith
• Mining Machinery

82. A tensile test is performed on a mild steel round bar. Its diameter after fracture will

• remain same
• increase
• decrease
• depend upon rate of loading

Solution

• Sannith
• Mining Machinery

83. The compression test is carried on __________ materials.

• Ductile
• Brittle
• Malleable
• Plastic

Solution

• Sannith
• Mining Machinery

84. In order to know whether a column is long or short, we must know its Slenderness ratio.

• True
• False

Solution

• Sannith
• Mining Machinery

85. When a point load on the free end of a cantilever beam is increased, failure will occur

• At the free end
• At the fix end
• In the middle of the beam.
• At a distance 2l/3 from free end

Solution

• Sannith
• Mining Machinery

86. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress will be

• 400 MPa
• 500 MPa
• 900 MPa
• 1400 MPa

Solution

• Sannith
• Mining Machinery

87. A steel bar of 5 mm is heated from 25°C to 45°C and it is free to expand. The bar will induce

• No stress
• Shear Stress
• Tensile stress
• Compressive stress

Solution

• Sannith
• Mining Machinery

88. Strain energy is the

1. Energy stored in a body when strained within elastic limits
2. Energy stored in a body when strained up to the breaking of a specimen
3. Maximum strain energy which can be stored in a body
4. Proof resilience per unit volume of a material

Solution

• Sannith
• Mining Machinery

89. The volumetric strain is the ratio of the

1. Original thickness to the change in thickness
2. Change in thickness to the original thickness
3. Original volume to the change in volume
4. Change in volume to the original volume

Solution

• Sannith
• Mining Machinery

90. The power source in a pneumatic system is____

• Air receiver
• Compressor
• Valve
• Muffler

Solution

• Sannith
• Mining Machinery