Chapter 26, Problem 8RAT

When stress exceeds a rock's strength, the rock body

(a) Breaks, which forms a fault

(b) Permanently changes its form-it breaks or flows.

(c) Becomes brittle, creating folded rock layers

(d) Becomes plastic.

To determine

The correct option for the statement "When stress exceeds a rock's strength, the rock body".

Answer to Problem 8RAT

The correct option for the statement "When stress exceeds a rock's strength, the rock body" is (b).

Explanation of Solution

An internal force applied by the molecules of the object when an amount of force applied on an object is known as the stress. The rock either breaks or flows permanently, changing its form when the stress exceeds strength of a rock.

According to the given options (a), (d) and (c), it can not be determined that the rock may break or can deform plastically under excessive stress, so the option (a), (d) and (c) options are incorrect. So the option (b) for this statement is the right option.

Conclusion:

Therefore, the correct option for the statement "When stress exceeds a rock's strength, the rock body by" is option (b).