It exchanges the cations or the anions of two ionic compounds.
Box 1 (having a mass of 10 kg) will slide first as it has less inertia than the other box. It will also require less force to overcome static friction between the surface of the plank and that of the first box.
I think it is d but not sure
It is because both of them are attracted towards earth where the heavier body gravity field influence is more in comparision to small. For eg; there are two magnet with less power in besides of huge power or magnetic influence then both of the less power magnet are attracted towards the huge one rather than attracting themselves.
Hope its helps u!
