Let the mass of the heavy object be m.
Thus, the weight of the object or the pull of the floor on the object is W=mg
Now, if g becomes twice, then the weight of the object or the pull of the floor on the object also becomes twice
i.e. W ′ =2mg=2W Thus, because of doubling of the pull on the object due to the floor,
it will become two times more difficult to pull it along the floor.