Which weighs more feathers or rocks?

Answer 1

Answer That seems like a trick question to me! You could certainly gather enough feathers to equal the 'weight' of a rock. Weight is a measure of gravitational force on an object. The pull of gravity on a rock and a feather will be the same. In a vacuum, they will both fall at the same rate. They will both hit the bottom at the same time. Now of course, rocks feel heavier than feathers. But you could gather enough feathers so that a box of feathers feels just about as heavy as a rock. So which weighs more? Feathers or rocks? The question you should probably ask is which has more 'mass'. A measure of mass doesn't change with altitude, as does weight. Mass will be the same measurement for an object no matter where you take the measurement. And even better, you should probably ask which has the bigger density. Density is mass per volume. And then, of course, the answer is easy to give: rocks have a bigger density than feathers. Because if you take a box filled with rocks and a box filled with feathers, and if both boxes have the same size (the same volume) then the box with rocks is going to have the bigger mass.