A student is preparing a scale diagram for a school project.
(i) On her drawing sheet she uses the scale 1cm=5m. She draws an arrow 4.8cm long from point A to point B towards the east to show the displacement of a boy walking in the playground. Calculate the magnitude of the displacement represented by the arrow.
(ii) On the same sheet she wishes to represent a velocity of 18m/s towards the north-east using a different scale, 1cm=2m/s. What should be the length of the arrow she must draw?
(iii) If both arrows of parts (i) and (ii) are drawn on the same sheet without changing either scale, will the two arrows correctly represent the two different physical quantities? Give a reason for your answer.