A ship leaves harbour and sails due north to point
PHYSICS · Multi-part · CBSE · Physics · Motion in a Plane · Motion in a Plane
Problem
A ship leaves harbour O and sails 12km due north to point P, then 9km due west to point Q. From Q it wishes to reach a station S that is located directly 15km due east of O.
(i) Represent the three known displacements OP, PQ and OS in vector form, taking east as the positive x-axis and north as the positive y-axis.
(ii) By drawing the first two displacements to scale, determine graphically the single displacement QS that the ship must undertake from Q to arrive at S. State its magnitude and direction correct to the nearest tenth of a kilometre and to the nearest degree.
(iii) Verify your graphical answer in part (ii) by analytical computation using vector components.
(iv) Find the total distance travelled by the ship and its net displacement from O to S. Comment briefly on the difference between the two quantities.