![TIL that one of the first prototype looping roller coasters had a perfectly circular loop. As a result, riders were exposed to approximately 12gs of force, and frequently suffered neck injuries while TIL that one of the first prototype looping roller coasters had a perfectly circular loop. As a result, riders were exposed to approximately 12gs of force, and frequently suffered neck injuries while](https://external-preview.redd.it/Nr5nHQiya65wS129bsn1SFE11x6Pa3gJiCqUmOZwpdo.jpg?auto=webp&s=fbbef2a0ba558e95e6787bc13a64d20127200578)
TIL that one of the first prototype looping roller coasters had a perfectly circular loop. As a result, riders were exposed to approximately 12gs of force, and frequently suffered neck injuries while
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Tennis Ball Rolling Looping Video with No Logo or Text. Isolated on White Background. Tennis Ball Rolling with Alpha Stock Video - Video of white, recreation: 222487143
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