A hard material has a _______ modulus of elasticity, whereas a soft material has a _______ modulus of elasticity.

A hard material typically exhibits a high modulus of elasticity because it is stiffer and more resistant to deformation under applied loads. The modulus of elasticity, often called Young's modulus, quantifies the relationship between stress (force per unit area) and strain (deformation) in a material. In hard materials like steel or concrete, the atoms are tightly packed, resulting in a strong atomic bond that contributes to a higher resistance to elastic deformation.

In contrast, a soft material has a low modulus of elasticity. Soft materials, such as rubber or foam, have a greater ability to deform under stress, indicating that they are more flexible and less resistant to elastic deformation when force is applied. The less tightly packed atomic structure or the nature of the bonding in soft materials leads to lower stiffness and, consequently, a lower modulus of elasticity.

This relationship reflects fundamental properties of materials and their behavior under load, making the distinction between hard and soft materials critical in structural engineering and material selection.