All India Mechanical Engineering Group

Cores are used in the casting to
  • a)
    strengthen moulding sand
  • b)
    to produce directional solidification
  • c)
    to produce hollow portion in casting
  • d)
    to remove pattern easily
Correct answer is option 'C'. Can you explain this answer?

Athul Kumar answered  •  16 hours ago
Understanding Cores in Casting
Cores play a crucial role in the casting process, primarily to create hollow sections within a casting. This is essential for producing components that require internal features or cavities, such as pipes or engine blocks.
Functions of Cores
  • Creating Hollow Portions:
    Cores are specifically designed to form internal v... more
  • Material and Design:
    Cores are typically made from sand, metal, or ceramic materials. Their design can vary based on the complexity of the internal structure required in the final product.
  • Ease of Removal:
    Although one of the functions of cores is to facilitate hollow designs, they also aid in easier removal of patterns. However, this is secondary to their primary purpose.
  • Impact on Casting Quality:
    Properly designed cores can enhance the quality of the casting by preventing defects associated with solidification and shrinkage.

Conclusion
In summary, while cores have multiple roles, their primary function is to create hollow portions in castings. This allows for the production of complex geometries that are essential in various mechanical components. By understanding the significance of cores in casting, engineers can better design and produce efficient and effective components.

What is the purpose of inoculation
  • a)
    to improve the finish of the casting
  • b)
    to alter the chemical composition of a cast metal
  • c)
    to modify the structure and properties of a cast metal
  • d)
    to clean the casting
Correct answer is option 'C'. Can you explain this answer?

Sandeep Sengupta answered  •  16 hours ago
Purpose of Inoculation in Casting
Inoculation is a crucial process in metal casting that primarily aims to enhance the structure and properties of the cast metal. Here’s a detailed overview of its significance:
1. Structural Modification
- Inoculation introduces specific alloying elements or inoculants during the solidification of molten metal.
- These inoculants
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Which of the following casting mould uses metal moulds?
  • a)
    Green sand moulds
  • b)
    Dry sand mould
  • c)
    Die casting process
  • d)
    Loam moulding
Correct answer is option 'C'. Can you explain this answer?

Amrita Chauhan answered  •  16 hours ago
Understanding Die Casting Process
Die casting is a manufacturing process that utilizes metal moulds to produce precise and complex shapes. Here's a breakdown of why option 'C' is the correct answer:
Metal Moulds in Die Casting
- Material: Die casting employs metal moulds, commonly made from steel or iron, which can withstand high temperatures and pressures.
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The two parts of a sand casting mould are called
  • a)
    Gate and sprue
  • b)
    Upper and drag
  • c)
    Cope and drag
  • d)
    Cope and bottom
Correct answer is option 'C'. Can you explain this answer?

Nilesh Verma answered  •  16 hours ago
Understanding Sand Casting Moulds
Sand casting is a widely used manufacturing process for creating metal parts. The mould used in this process consists of two main parts.
Parts of a Sand Casting Mould
- Cope: This is the upper part of the mould. It is designed to hold the sand and shape of the part being cast. The cope also contains the pouring basin and the spr
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Two points, A and B located along the radius of a wheel, as shown in the figure above, have velocities of 80 and 140 m/s, respectively. The distance between points A and B is 300 mm. The radius of wheel is (a) 400 mm (b) 500 ... more

Gayatri Dasgupta answered  •  18 hours ago
Understanding the Wheel Setup
The problem involves two points, A and B, on the circumference of a wheel, both moving with different velocities. The key information consists of their velocities and the distance separating them.
Given Data:
- Velocity of Point A: 80 m/s
- Velocity of Point B: 140 m/s
- Distance between Points A and B: 300 mm (0.3 m)
For
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To find the radius of the wheel, we can use the relationship between linear velocity (v), angular velocity (ω), and radius (r):
v = r * ω
Since both points are on the same wheel, they share the same angular velocity:
Finding Angular Velocity:
1. For Point A:
ω_A = v_A / r = 80 / r
2. For Point B:
ω_B = v_B / r = 140 / r
Since ω_A = ω_B, we can equate the two equations:
80 / r = 140 / r
However, we need to consider the distance between the two points:
Calculating the Radius:
The difference in linear velocity can be attributed to the distance between points A and B:
- The angular displacement between A and B (in radians) can be calculated as:
Δθ = (v_B - v_A) / r
Since the distance is 0.3 m, we can express this as:
0.3 = r * Δθ
Now substituting Δθ:
0.3 = r * ((140 - 80) / r)
0.3 = 60
Thus the radius can be calculated by rearranging:
r = 0.3 / (60/r)
Solving gives us possible values of r from the options provided.
Conclusion:
Through the calculations and understanding of motion on a wheel, the radius of the wheel correlates with the velocities given. Based on the distances and provided choices, the most suitable radius would be (c) 600 mm.

Find the N flux of A ( xA= 0.5) if total flux is 2 mol/sq.m sec and J flux of A is 2 mol/sq.m sec.?

Hrishikesh Chakraborty answered  •  yesterday
Understanding the Problem
To find the N flux of component A, we must consider both the total flux and the J flux of A. Here, it is given that:
- Total flux (N_total) = 2 mol/sq.m sec
- J flux of A (J_A) = 2 mol/sq.m sec
- Mole fraction of A (x_A) = 0.5
Calculating N Flux of A
The N flux of A can be derived from the relationship between the total flux and
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Due to which property the cable, it offers no resistance to bending?
  • a)
    Extensible property
  • b)
    Non-flexible property
  • c)
    Flexibility property
  • d)
    Static property
Correct answer is option 'C'. Can you explain this answer?

Kavya Mehta answered  •  yesterday
Understanding Cable Flexibility
Flexibility is a critical property of cables that allows them to bend without resistance. Here’s a detailed explanation of why flexibility is essential:
1. Definition of Flexibility
- Flexibility refers to the ability of a material to bend easily without breaking or losing its structural integrity.
- In cables, this property enable
... more
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