Final answer:
A beam is what transfers a load perpendicularly to an imposed load, creating compressive and tensile forces. The top surface of a beam is under compressive stress while the bottom surface is under tensile stress. Shear deformation involves a shift of layers in response to antiparallel forces applied tangentially to an object.
Step-by-step explanation:
A beam transfers a load perpendicularly to an imposed load, creating compressive and tensile forces within it. This is due to the way beams support weight and handle the stress of loads placed upon them. For example, when a long shelf is loaded with heavy books, it may sag between the end supports under the weight. The top surface of the shelf is under compressive stress because it is being squeezed together, and the bottom surface is under tensile stress because it is being stretched. Similarly, heavy beams sag under their own weight, but the use of modern I-beams can minimize these bending strains.
When we refer to shear deformation, we are talking about a situation where two antiparallel forces of equal magnitude are applied to opposite surfaces of an object, leading to a shift of layers in the direction tangent to the forces. This type of deformation is characterized by the gradual shift Ax of layers along some distance Lo.
Understanding the types of stress and deformation such as tension, compression, and shear is crucial for designing structures that are capable of withstanding various loads without failing.