Final answer:
Normal stresses can be measured with a strain gauge, which is an electrical device that changes its resistance when stretched. Strain gauges are affected by temperature changes, and temperature compensation techniques are used to ensure accurate stress measurements.
Step-by-step explanation:
Normal stresses can indeed be measured with a component called a strain gauge. A strain gauge is an electrical device that measures strain, which is a unitless quantity defined as the ratio of the change in length to the original length. When a material is subject to stress, it deforms, and this deformation is characterized by strain. Strain gauges work by having a flexible, insulating backing that supports a conduction foil pattern. As the backing is stretched, the resistance of the foil changes. This change in resistance can be measured and correlated to the amount of strain, providing a quantitative measure of stress experienced by the material.
Regarding the effect of temperature on strain gauges, they are indeed affected by temperature changes. As temperature changes, it can cause expansion or contraction of the strain gauge material, thereby affecting its resistance independently of the strain. To ensure accurate measurements, strain gauges are often paired with temperature compensation techniques.
In conclusion, the answer to the student's question is: a) True