Ethan is helping his father rearrange the furniture in their living room. They have two different tables that are the same size. When Ethan pushes on each table, he finds that it is harder to move table A than it is to move table B. Why does Ethan have to push with more force on table A than on table B? a Table A has more volume than table B. b Table A has more mass than table B. c Table A weighs less than table B. d Table A is less dense than table B
b) Table A has more mass than table B.
The difficulty in moving an object by pushing on it is related to its inertia, which is a direct consequence of its mass. The more mass an object has, the more force is required to overcome its inertia and start it moving, or change its velocity if it's already in motion. Volume, weight (which is affected by gravity), and density are not directly related to the difficulty of moving an object on a flat surface; mass is the key factor. Even if two objects have the same size (volume), the one with more mass will be harder to move. Weight is a force due to gravity acting upon the mass of the object, but since both tables are in the same gravitational field and we are considering the effort to move them horizontally, the actual weight does not explain the difference in difficulty. Density is related to mass and volume, but again, since they have the same volume, it's the difference in mass that matters here, not density.