Tough physics question

Question

A motorcycle moving initially at 64 km/h [N], turns a corner and continues at 64 km/h [E]. The turn takes 8.0 s to complete. Find



(a) the change in velocity (3 marks)

(b) the average acceleration during the turn (2 marks)

Answer 1

First let's turn the velocity into m/s (SI unit)

64 km/h = 64000 m / 3600 s ≈17.8 m/s

a) The change in velocity vector when the motorcycle turns from N to E is the hypothenuse of an isosceles right triangle. Therefore, the change in velocity (for displacement) is 17.8 x √2 ≈ 25.2 m/s ( North East 45degrees from horizontal )

b) a_(av) = Change in V/time = 25.2/8 = 3.15 m/s² ≈ 3.2 m/s²