Question

The diagram below shows the path taken by a boat sailing from port

A.The boat takes 1.5 hours to travel from port A

to port B. It immediately sails from port

B towards port C. The boat takes 2.0 hours

to travel from B to C. The distances travelled for each section of the journey are

shown on the diagram.

As the boat sailed from A to C

, calculate:

a. its average speed in m s−1

b.the magnitude of its displacement.

Answer 1

a. $v_{avr}=\frac{30+40}{1.5+2}=20\ (km/h)=5.6\ (m/s)$

b. $d=\sqrt{30^2+40^2}=50\ (km)$