Question

A boy moves 3 km North, then turns right and moves 4 km, then turns right again and moves 3 km. How far is he from the starting point?

• A. 3 km
• B. 4 km
• C. 5 km
• D. 6 km

Hint:

Break movements into perpendicular components to calculate resultant displacement.

Answer 1

The Correct Option is B

Step 1: The boy starts at a point and moves 3 km North.
Step 2: Turns right (facing East) and moves 4 km.
Step 3: Turns right again (facing South) and moves 3 km.
This brings him back in line with the original horizontal axis.
Step 4: Calculate displacement:
North-South displacement = \(3 - 3 = 0\) km (he is aligned horizontally with start)
East-West displacement = 4 km East
Step 5: Distance from starting point = 4 km.