The circumferential and longitudinal strains in a cylindrical boiler under internal steam pressure are εc and εl respectively. The change in volume of the boiler cylinder per unit volume will be
εc + 2εl
2εc + εl
εc + εl²
εc² + εl
Correct Answer :
B. 2εc + εl
Related Questions
The crest diameter of a screw thread is same as
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Minor diameter
Pitch diameter
Core diameter
In the levers of third type, the mechanical advantage is __________ one.
Less than
Equal to
More than
None of these
A connecting rod is designed as a
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Short column
Strut
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Compressive stress
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Has head at one end and other end fits into a tapped hole in the other part to be joined
Has both the ends threaded
Has pointed threads
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One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming
A slot is cut partly in middle of nut and then slot reduced by tightening screw
A hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip
Through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at the other end
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Upper leaf
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M8
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Nipple joint
Union joint
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Both ends hinged
Both ends fixed
One end fixed and the other end hinged
One end fixed and the other end free
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20 to 30%
10 to 20%
30 to 40%
40 to 50%
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(k₁ - k₂)/ (k₁ + k₂)
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0.4
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0.75 t for wide strap on the inside and 0.625 t for narrow strap on the outside
0.75 t for both the straps on the inside and outside
0.625 t for both the straps on the inside and outside
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Butt joint with double cover plate
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3000-4000 kg/cm²
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Mitre gears
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Brinell hardness number
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Twisting moment only
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