Question

On his fishing trip Justin rides on hist 12 km south. The fish aren't biting so he changes location and goes 4 km west. What is Justin's displacement?

Answer 1

Justin's displacement is 12.65 km.

Explanation:

Since Justin rides 12 km south, then 4 km west, his displacement can be determined by applying Pythagoras theorem to the sketch of his journey. Let his displacement be represented by s,

`/Hyp/^(2)` =
`/Adj1/^(2)` +
`/Adj2/^(2)`

`s^(2)` =
`/4/^(2)` +
`/12/^(2)`

= 16 + 144

`s^(2)` = 160

⇒ s =
`√(160)`

= 12.6491

s ≅ 12.65 km

Justin's displacement is 12.65 km.