Direction Master - Quick Revision
Direction Master - Quick Revision
One-Liners
- Sun rises in the East → your left hand points North at sunrise.
- Clockwise turn from North is East → South → West → North.
- Anti-clockwise is the reverse: West → South → East → North.
- Right angle turn = 90°; U-turn = 180°.
- Shadow at sunrise is West; at sunset is East.
- Pythagoras gives shortest distance: √(x² + y²).
- Opposite directions: N-S, E-W, NE-SW, NW-SE.
- Left & Right swap when person faces you.
- Map convention: North always up.
- Even 90° turns (0°, 180°, 360°) leave original direction.
- Odd 90° turns (90°, 270°) flip N ↔ S or E ↔ W.
- 45° turn from North gives NE/NW.
- Distance = count of unit steps; displacement = straight-line from start.
- Left of North is West; right of North is East.
- Evening shadow falls East; morning shadow West.
- After 12 hrs the hour hand makes 180° (opposite direction).
- Minute hand 90° = 15 min; 180° = 30 min.
- Compass bearing 0° = North; 90° = East; 180° = South; 270° = West.
- NE is 45°; SE 135°; SW 225°; NW 315°.
- Sum of all exterior turns in a closed path = 360°.
| Formula | Use |
|---|
| Shortest distance = √(ΔE-W² + ΔN-S²) | Straight-line displacement |
| New direction = (Initial° + Clockwise°) mod 360 | After any turn |
| Relative bearing = (Observer bearing – Target bearing + 360) mod 360 | Bearing of target |
| Shadow direction = 180° – Sun’s bearing | Opposite to sun |
| Left of North = 315° (NW); Right of North = 45° (NE) | 45° turns |
| After 90° right from North → East; left → West | Quick 90° rule |
| Closed-loop displacement = 0 | Return to start |
| Sum of exterior angles = 360° | Any polygon path |
| Mirror direction = 360° – original bearing | Reflection rule |
Memory Tricks
- “Never Eat Soggy Worms” – clockwise order North-East-South-West.
- “Left-hand rule” – extend left arm at sunrise → points North.
- “L-90” – Letter L turns Left 90° from North → West.
- “OPPOSITE” – first & last letters O-E → West is opposite East.
- “4-45s make 180” – four 45° turns = half circle (U-turn).
Common Errors
| Error | Correct |
|---|
| Assuming left/right same when person faces you | Swap sides (mirror) |
| Using total distance instead of displacement | Use Pythagoras for shortest |
| Forgetting mod 360 after big turns | Always reduce bearing mod 360 |
| Counting 45° as 90° | 45° is halfway to 90° |
| Shadow same as sun direction | Shadow is 180° opposite sun |
5 Quick MCQs
Q1. A man walks 10 m South, then 10 m West, then 10 m North. Where is he from start?
**A)** 10 m WestQ2. After two right-angle clockwise turns from facing East, you face?
**A)** WestQ3. Shortest distance between start and finish after 9 m East + 12 m North?
**A)** 15 mQ4. Sun rises from East; shadow of a pole will be toward?
**A)** WestQ5. If North becomes South-East on a rotated map, the map has turned how many degrees clockwise?
**A)** 135°
BETA
