At 5 p.m., Mr. Floyd is standing facing a tower. His shadow falls exactly to his right. After 30 minutes, he turns 180° and start…

Question

At 5 p.m., Mr. Floyd is standing facing a tower. His shadow falls exactly to his right. After 30 minutes, he turns 180° and starts walking straight. In which direction is he walking?

1. A. East
2. B. North
3. C. South (Correct answer)
4. D. West

Correct Answer

Option C — South

Detailed Solution & Explanation

The correct answer is South.

Key Points

• Step 1 — locate the shadow. At 5 p.m. the Sun is in the west, so all shadows fall towards the east.
• Step 2 — find the direction he faces. His shadow falls exactly to his right, so east lies to his right. If a person's right hand points east, they must be facing north.
• Step 3 — apply the turn. After 30 minutes he turns 180°, which reverses his facing direction:
  • $\text{North} \xrightarrow{\;180°\;} \text{South}$
• He therefore walks towards the south.

Shortcut Trick

• Remember the two anchors: shadow falls west in the morning (Sun in the east) and shadow falls east in the evening (Sun in the west). Then use the hand rule — if you face north, east is on your right and west on your left; if you face south, the two are reversed.

Additional Information

• The 30-minute delay is deliberately irrelevant. At 5.30 p.m. the Sun is still in the west, so the shadow direction is unchanged. Extra detail of this kind is inserted to see whether candidates track what actually matters.
• Shadow-based direction rules:
  • Sunrise (6 a.m.) — Sun in the east, shadows fall west.
  • Noon (12 p.m.) — Sun overhead, shadow is minimal; in the Northern Hemisphere it falls slightly north.
  • Sunset (6 p.m.) — Sun in the west, shadows fall east.
• Turn conventions: a 180° turn reverses direction (north ↔ south, east ↔ west); a 90° clockwise turn moves north → east → south → west → north; a 90° anticlockwise turn reverses that cycle.