Runner A starts from the origin at s and moves with constant velocity

MATHEMATICS · Multi-part · A Level · Mathematics · Kinematics · Kinematics

Problem

Runner A starts from the origin at

t = 0

s and moves with constant velocity

4\,\text{m s}^{-1}

. Runner B is

20\,\text{m}

ahead of A at

t = 0

s and moves such that its velocity (in m s

^{-1}

) is given by

v_B = 6 - 0.2t

. (i) Find the time when A draws level with B. (ii) State their common position at that instant.