D8 QUIZ OF THE DAY

Which property differentiates true specific gravity from apparent specific gravity?

• Inclusion of all pores
• Exclusion of pores
• Inclusion of surface moisture
• Inclusion of air voids

Answer explanation

True specific gravity excludes all types of pores, while apparent specific gravity includes them.

What is the significance of coefficient of softening being unity for a material?

• Material softens rapidly
• No water absorption
• Strength remains same when wet
• High porosity

Answer explanation

A coefficient of softening equal to 1 means the compressive strength remains unaffected by water saturation.

The plasticity of a material increases with:

• Decrease in temperature
• Increase in tensile stress
• Increase in temperature
• Increase in porosity

Answer explanation

Plasticity generally increases with temperature, enabling more deformation without failure.

Which material property is most critical in selecting bricks for fire-resistant construction?

• Density
• Compressive strength
• Refractoriness
• Thermal conductivity

Answer explanation

Refractoriness is key for fire resistance, especially in high-temperature environments.

Which of the following is true about malleability?

• Ability to be drawn into wire
• Related to tensile stress
• Enhances under freezing
• Measured under compressive stress

Answer explanation

Malleability is the property of being flattened into sheets under compressive force.

Which property is tested using the Izod test?

• Fatigue
• Impact strength
• Hardness
• Creep

Answer explanation

Izod and Charpy tests are used to assess impact strength of materials.

A material with high porosity will generally have:

• High bulk density
• High strength
• Low thermal conductivity
• High water absorption

Answer explanation

High porosity leads to increased water absorption and lower mechanical strength.

Which of the following statements is true regarding thermal conductivity?

• It is unaffected by porosity
• It decreases with moisture
• Porous dry materials have low thermal conductivity
• All materials have same conductivity

Answer explanation

Porous dry materials trap air, reducing heat transfer.

Why is Bakelite preferred for electric insulation?

• Flexible and reusable
• Thermoplastic behavior
• High impact resistance
• Thermosetting and non-conductive

Answer explanation

Bakelite is a thermosetting plastic with excellent insulation properties.

In which property does steel outperform all traditional building materials?

• Thermal conductivity
• Compressive strength
• Modulus of elasticity
• Flexibility

Answer explanation

Steel has a very high modulus of elasticity, indicating great stiffness.