Question

why is weight a vector quantity ?..plz explain conceptually

Answer 1

Well weight is a force resulting from the product of mass and gravitational acceleration. Hence,
Gravity tends to pull objects towards its source(in this case the source being the earth). Therefore, its acceleration is exerted upon the object in a particular “direction”. And this direction is towards its source.
From the basic definition of Vector quantities, we know that they possess both magnitude and direction. Weight is an extrinsic property which depends upon the intrinsic property i.e. mass. This gives it magnitude.
Therefore, as weight contains both magnitude and direction, it is essentially a vector quantity.