INTERVIEW QUESTIONS OF STRENGTH OF MATERIAL

• A bearing is designated as 6205 , what is its bore diameter:

Generally for bearing bore diameter is 5 times the last number in its designation i.e. for designation 6205, Bore diameter should be 25

• Where half nut is used?

the half hut is use in lathe .in this half nut mechanism is engaged during the thread cutting operation.and it connect carriage and lead screw.it having 2 portion one half is fixed and one movable.

• Why the rail in form of I-beam?

It’s flexural rigidity is high and it’s cross section consume low metal.

• Aluminium foil used for cooking food and storage has one shiny surface and one dull surface. Which surface side be on the outside when the food is wrapped for baking and freezing respectively.
  1. Shiny side, shiny side
  2. Dull side, dull side
  3. Shiny side, dull side
  4. Dull side, shiny side

Answer:

Dull side, Shiny side

Reason:

• The shiny surface of foil loses heat through radiation much faster than the dull surface.
• When the food is baked shiny surface is kept inside, so the heat is kept inside and not to leave.
• When the food is freeze shiny surface kept outside, so the loss of heat is radiated faster which keeps the food in cool.

• What is difference between pressure and stress?

When the force or load acting on the fluid(pneumatic or hydraulic)per unit area is known as PRESSURE.. It's purely subjected to fluids.

When the force or load acting on the object(solid) within the elastic limit of an object create internal resistance to resist the apply load. that internal resistance is known as STRAIN for per unit area of that object.. Its mainly subjected to solids…

• Is there any rake angle in blade? which is used to shave the beard ?

It consists of negative rake angle.

• Stress strain diagram for fluid

PARALLEL LINE HORIZONTAL TO STRESS AXIS

• What’s the range of poisons ratio of a stable material?

Theoretical values are — -1 to 0.5

Practical values are — 0 to 0.5

• Why 220 V A.C. is more dangerous than 220 V D.C
  1. The D.C. attracts
  2. Peak voltage for A.C. is much larger
  3. The body offers less resistance to A.C.
  4. Due to some other reasons

Answer:

Peak voltage for A.C. is much larger

Reason:

D.C. = 220 volt

A.C. = 1.414 x 220 volt

• What is the difference between limit of proportionality and elastic limit

Up to the limit of proportionality stress is directly proportional to strain,follows hooks law,elastic limit is limit for elasticity of material.