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چار آپشن میں سے کسی ایک پر کلک کرنے سے جواب سرخ ہو جائے گا۔
بھاپ کے لئے تنقیدی دباؤ _____ ہے؟
- 163 bar
- 252 bar
- 225 bar
- None of these
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Explanation
The critical pressure of steam is about 22.1 MPa (≈ 221 bar).
At this pressure, the distinction between liquid and vapor disappears.
ریئر وہیل ڈرائیو کے مقابلے میں ، فرنٹ وہیل ڈرائیو _____؟
- Has increased tractive effort when going up steep gradient
- Has better riding performance
- Greater sliding tendency
- None of these
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Explanation
In front-wheel drive, engine weight is over the driving wheels, improving traction on slopes.
This gives better grip while climbing compared to rear-wheel drive.
حج ڈی ایم میں چنگاریاں کی اوسط تعدد _____ ہے؟
- 1000 sparks per second
- 4000 sparks per second
- 2000 sparks per second
- None of these
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Explanation
In EDM, material is removed by rapid electric sparks between tool and workpiece.
The average spark frequency is about 1000 sparks per second under normal conditions.
مندرجہ ذیل میں سے کون سا عمل بنیادی طور پر سطح کی تکمیل کو حاصل کرنے کے لئے استعمال ہوتا ہے؟
- Broaching
- Hobbing
- Honing
- None of these
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Explanation
Honing is a finishing process used to improve surface finish and dimensional accuracy of holes.
It removes small amounts of material to produce a smooth and precise surface.
شیپر اور منصوبہ ساز کے مابین مندرجہ ذیل میں سے کون عام ہے؟
- Both use single point cutting tool
- Both have stationary tool
- Both have reciprocating work piece
- None of these
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Explanation
Shapers and planners both employ a single-point cutting tool to remove material.
The main difference is shaper has a moving tool, while planner has a moving workpiece.
- Feed
- Chip velocity
- Cutting velocity
- None of these
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Explanation
Cutting velocity is the speed at which the cutting tool moves relative to the workpiece.
It is a critical factor in machining efficiency, surface finish, and tool life.
لام سانچوں کا استعمال _____؟
- In centrifugal castings
- For small size articles
- For large castings
- None of these
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Explanation
Loam moulds are strong and can withstand high temperatures, making them suitable for large castings.
They are usually used in foundries for heavy and complex-shaped castings.
مندرجہ ذیل میں سے سبھی نچوڑ آپریشن کے سوا ہیں؟
- Crimping
- Stamping
- Swaging
- Trimming
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Explanation
Squeezing operations involve deforming material by compressive forces (Crimping, Swaging, Trimming).
Stamping mainly involves cutting or punching, not squeezing.
اخراج چیمبر ، ڈائی اور رام عام طور پر _____ کے ذریعہ چکنا ہوتا ہے؟
- Kerosene oil
- Grease
- Solid lubricant
- None of these
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Explanation
Kerosene oil is commonly used to lubricate the extrusion chamber, die, and ram.
It reduces friction and prevents overheating during metal extrusion.
دھاتوں کا سرد کام کیا جاتا ہے؟
- Working temperature depends upon physical conditions of the work piece
- Below the recrystallisation temperature
- At the recrystallisation temperature
- None of these
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Explanation
Cold working strengthens metals by plastic deformation below their recrystallization temperature.
It increases hardness and tensile strength but reduces ductility.
