What is heavier 100 pound of rocks or 100 pounds of feather?

Both 100 pounds of rocks and 100 pounds of feathers weigh the same amount, which is 100 pounds. Weight is a measure of the force of gravity acting on an object, and in this case, both sets of objects have the same weight. The difference lies in their densities, with rocks being much denser than feathers, which is why a smaller volume of rocks weighs the same as a larger volume of feathers.