In which situation would a pry bar be ineffective?

A pry bar is a tool primarily used for leverage, and its effectiveness depends on the length of the bar relative to the distance and force required to lift or move an object. When a pry bar is too short, it may not provide enough leverage to effectively lift or pry the object, making it challenging to move or reposition it as intended. The ideal length allows the user to apply force at a greater distance from the pivot point, which is critical for achieving the necessary mechanical advantage.

The effectiveness of a pry bar does not necessarily diminish for light rocks, smooth surfaces, or small rocks. In fact, lighter objects can often be moved with lesser force, and smooth surfaces may allow for easier sliding when using a pry bar. Small rocks may also still be lifted or repositioned with a properly utilized pry bar. It's primarily the length of the pry bar that determines its capacity to handle larger leverage tasks effectively.