### Interview Questions (Design of Machine Elements)

**Explain notch sensitivity. State the relation between stress concentration factor and notch sensitivity.**

Notch sensitivity (q) is the degree to which the theoretical effect of stress concentration is actually reached.

The relation is, K

_{f}- 1 + q(K

_{t}- 1)

**What are the factors that affect notch sensitivity?**

The factors affecting notch sensitivity are:

- Material
- Notch radius
- Size of component
- Type of loading
- Grain Structure

**What are the different types of loads that can act on machine components?**

Different loads on machine components are:

- Steady load.
- Variable load.
- Shock load
- Impact load.

**Define machinability**

It is the property of the material, which refers to the relative ease with which a material can be cut. It is measured in a number of ways such as comparing the tool life for cutting different material.

**What is an S-N Curve?**

An S- N curve has fatigue stress on ‘Y’ axis and number of loading cycles in 'X' axis. It is used to find the fatigue stress value corresponding to a given number of cycles.

**What is curved beam?**

In a curved beam, the neutral axis does not coincide with the centroidal axis.

**Give some example for a curved beam.**

C frame, crane hook

**What are the principle stress and principle plane?**

A plane which has no shear stress is called principle plane the corresponding stress is called principle stress.

**Write the bending equation.**

The bending moment equation is,

Where,

M - Bending moment (M is in N-mm)

I - Moment of inertia about a centroidal axis (mm

^{4})

f - Bending Stress (N/mm

^{2})

y - Distance from neutral axis (y is in mm)

E - Young's modulus (N/mm

^{2})

R - Radius of curvature (mm)

**Write the torsion equation.**

The torsional equation is,

Where,

T - Torsional moment (N- mm)

J - Polar moment of inertia (mm

^{4})

q - Shear stress in the element (N/mm

^{2})

r - Distance of element from the centre of shaft (mm)

G- Modulus of Rigidity (N/mm

^{2})

θ - Angle of twist (radians)

L - Length of the shaft (mm)

Subscribe

## Comments

## Post a Comment