Physics

Problem

A roller-coaster car carrying passengers crests the top of a circular arc of radius

20\,\text{m}

. Neglecting friction, what minimum speed must the car have at the top so that the passengers just begin to feel weightless? a)

20\ \text{m/s}

10\ \text{m/s}

14\ \text{m/s}

28\ \text{m/s}