How 'pressure' is a scaler quantity?
It is a scalar since it is the force per unit area acting perpendicularly to a surface element, so the definition kind of has a direction "built in" if you know what I mean so that the quantity need not contain this directional information.
i am not clear.....
Well pressure is defined as pointing directly against a surface (at 90 degrees) which means that the direction is already defined so making pressure a vector would be redundant since if you know the position you know the direction.
It would be like having a packet of red frogs which have "red" written on each and every one of them, it's redundant.
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