A passenger's diamond ring was stolen on a cross-country train. The conductor searched every compartment while the train was at full speed between stations. He found the ring hidden inside the toilet paper roll in the caboose restroom. The suspect passenger smirked, saying, 'Anyone could have walked back there.' The detective arrested the suspect. Why?
Vibrational physics
A train moving at high speed rocks violently. An item simply stuffed loosely into a commercial toilet paper holder would have rattled out onto the floor within seconds, meaning it had to be wedged or placed there by someone currently sitting nearby.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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