Guys i really need your zealous help! It is a simple concept but i have some doubt on it. A vector can be resolve into its component vectors like unit vectors i,j & k. A single vector can be expressed into its i-components and j-components if it is a 2-dimensional vector. Is it when 2 vectors are equivalent, they must give the same consequences ? And when vectors are used to represent forces, a single force can be resolved into its x and y components. However if the force is acting perpendicular to the x-axis, supposedly it should have no y-components. But for inclined plane where the only force is the vertically downward gravitational pull on the object, we tend to resolve this vertical force into mg.cosθ or mg.sinθ which both these components vector having a horizontal components that cancel out each other! But in inclined plane, it do impart effect to the motion of the object. Why this could happens?? Lets say if we have a quantity 5 and we say this 5 is equal to quantity 10-5. But can that quantity 10 impart any effects on the current situation??