Two 1 mm thick steel sheets are to be spot welded at a current of 5000 A. Assuming effective resistance to be 200 μm and current flow time of 0.2 second, heat generated during the process will be
0.2 Joule
1 Joule
5 Joule
1000 Joule
Correct Answer :
D. 1000 Joule
Related Questions
Shrinkage allowance on pattern is provided to compensate for shrinkage when
The temperature of liquid metal drops from pouring to freezing temperature
The metal changes from liquid to solid state at freezing temperature
The temperature of solid phase drops from freezing to room temperature
The temperature of metal drops from pouring to room temperature
The grooving is an operation of
Bevelling the extreme end of a workpiece
Embossing a diamond shaped pattern on the surface of a workpiece
Reducing the diameter of a workpiece over a very narrow surface
Enlarging the end of a hole cylindrically
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500°C
900°C
1100°C
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Copper tungsten alloy
All of these
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Boron carbide
Silicon carbide
Any one of these
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Profile milling
Gang milling
Saw milling
Helical milling
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In-feed grinding
Through feed grinding
End-feed grinding
Any one of these
A push broach as compared to pull broach
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Is short and stocky
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All of the above
The main purpose of spheroidising treatment is to improve
Hardenability of low carbon steels
Machinability of low carbon steels
Hardenability of high carbon steels
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Grinding at high speed results in the reduction of chip thickness and cutting forces per grit.
Aluminium oxide wheels are employed.
The grinding wheel has to be of open structure.
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Surface grinder
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The chips are disposed off easily and do not interfere with the cutting.
The surface milled appears to be slightly wavy.
The coolant can be poured directly at the cutting zone where the cutting force is maximum.
Glazing in grinding wheels takes place when the
Wheel is too hard or wheel revolves at a very high speed
Wheel is too soft or wheel revolves at a very slow speed
Wheel is too hard and wheel revolves at very slow speed
Wheel is too soft and wheel revolves at a very high speed
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No relative motion occurs between them
No wear of tool occurs
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Low carbon steel
Titanium
Copper
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Break up chips
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Course grained
Fine grained
Medium grained
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0
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GMAW practice
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Increase machining accuracy
Facilitate interchangeability
Decrease expenditure on quality control
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Should always clear the width of the workpiece