Motion in a plane is also referred to as a motion in two dimensions. For example, circular motion, projectile motion, etc. For the analysis of such type of motion, the reference point will be made of an origin and the two coordinate axes X and Y. In this Chapter, we will come across questions related to the scalar and vector quantities in physics, performing algebraic expressions on various scalar quantities. We will be seeing questions on the magnitude of vectors and their co-linearity and will be finding the magnitude of the displacement vector of three girls skating in a circular ground and similarly framed question and there answers based on physics in this chapter.