Strength of Materials

What is the main purpose of the tension and compression test in engineering?

• To determine the relationship between average normal stress and average normal strain
• To determine the hardness of a material
• To measure the electrical conductivity of a material
• To test the durability of a material under high temperatures

What is the typical shape of the specimen used in a tension or compression test?

• Circular cross section with enlarged ends
• Square with sharp edges
• Rectangular with pointed ends
• Cylindrical with a taper at the middle

In a tension test, how is elongation (δ) measured?

• By using the change in length between two punch marks on the specimen
• By measuring the difference between the initial and final temperature
• By measuring the time it takes for the material to fail
• By calculating the total surface area of the material

What device is commonly used to measure the elongation in a tension or compression test?

• Extensometer
• Spectrometer
• Dynamometer
• Oscilloscope

How does an electrical-resistance strain gage measure strain during the tension or compression test?

• By detecting changes in the electrical resistance of the gage wire
• By measuring the temperature change in the material
• By directly reading the load applied on the specimen
• By measuring the change in pressure within the specimen

In the tension test of a metal specimen, which of the following is typically recorded?

• Applied load (P) and elongation (δ)
• Initial temperature and weight of the specimen
• Magnetic properties of the specimen
• Surface roughness and cross-sectional thickness

What does the gage-length distance (L₀) represent in a tension test?

• The initial length between two punch marks on the specimen
• The final length of the specimen after failure
• The distance between the specimen and the testing machine
• The diameter of the specimen’s cross-sectional area

In a tension test, why is the failure designed to occur in the central region of the specimen?

• To avoid failure near the clamped ends
• To prevent damaging the testing machine
• To test the resilience of the specimen at the ends
• To measure the temperature of the specimen more accurately

What is the engineering stress in a conventional stress–strain diagram calculated from?

• The applied load divided by the specimen’s original cross-sectional area
• The applied load divided by the specimen’s current cross-sectional area
• The elongation divided by the initial gage length
• The change in the specimen’s diameter during testing

What is the engineering strain in a tension test calculated from?

• The change in length divided by the specimen’s original gage length
• The change in length divided by the specimen's current length
• The initial gage length divided by the applied load
• The applied stress divided by the modulus of elasticity