In compression, a prism of brittle material will break

When a prism made of brittle material is subjected to compression, it will break. This is because brittle materials, unlike ductile materials, are unable to deform under stress. Instead, they fracture.

Here are the steps that lead to the breakage:

1. Stress Application: The process begins when a compressive force is applied to the prism. This force attempts to shorten the object along the axis of the applied force.

2. Elastic Deformation: Initially, the prism will undergo elastic deformation, meaning it will return to its original shape once the stress is removed.

3. Yield Point: If the stress continues to increase, the prism will reach its yield point, which is the maximum stress that the material can withstand without undergoing permanent deformation.

4. Fracture: Beyond the yield point, the brittle material does not deform plastically, but instead begins to crack. This is the beginning of the fracture process.

5. Breakage: The crack propagates rapidly through the material, leading to complete breakage. The prism of brittle material breaks because it cannot absorb the energy of the applied stress through plastic deformation.

So, in compression, a prism of brittle material will break due to its inability to deform under high stress. Instead, it cracks and ultimately breaks.