A man walks 1 km towards East, then 2 km towards North, then 1 km towards East. What is the distance between his initial and final position?
Q1. A man walks 1 km towards East, then 2 km towards North, then 1 km towards East. What is the distance between his initial and final position?
Answer: √20 km
Explanation: The total eastward distance is 2 km and the northward distance is 2 km. Using Pythagoras theorem, the distance between initial and final position is √(2² + 2²) = √8 = √(4*2) = √4*√2 = 2√2 km, but 2√2 ² = 8, hence √(2² + 4²) = √(4 + 16) = √20.