A marine research vessel monitors the positions of underwater sensors relative to a coastal lighthouse located at a fixed origin OOO.
Sensor P P\,P is located at position vector
OP→=(413) km \overrightarrow{OP} = \begin{pmatrix} 4 \\ 1 \\ 3 \end{pmatrix}\text{ km} OP=413 kmSensor Q Q\,Q is deployed such that its displacement from sensor P P\,P is given by
PQ→=(35−4) km \overrightarrow{PQ} = \begin{pmatrix} 3 \\ 5 \\ -4 \end{pmatrix}\text{ km} PQ=35−4 kmDetermine the coordinates of sensor QQQ.
A surface buoy R R\,R is located at position vector
OR→=(1k2) km \overrightarrow{OR} = \begin{pmatrix} 1 \\ k \\ 2 \end{pmatrix}\text{ km} OR=1k2 kmwhere k k\,k is a constant.
Given that the position vector of the buoy, OR→\overrightarrow{OR}OR, is perpendicular to the displacement vector between sensor Q Q\,Q and the buoy, QR→\overrightarrow{QR}QR,
find the possible values of kkk.
197 exam-style questions on OCR A Level Maths 1.10 Vectors, covering 1.10.1 Vectors in two dimensions, 1.10.2 Vectors in three dimensions (A-level only), 1.10.3 Magnitude and direction of vectors, 1.10.4 Basic operations on vectors, 1.10.5 Position vectors, 1.10.6 Distance between points, 1.10.7 Problem solving using vectors, 1.10.8 Vectors in kinematics, and 1.10 Vectors. Each one has a worked solution and a mark scheme showing where the marks go.