an electronic sensor is embedded in the seat of a car that takes riders around a circular loop-the-loop ride at an amusement park. the sensor measures the magnitude of the normal force that the seat exerts on a rider. the loop-the-loop ride is in the vertical plane and its radius is 25 m. sitting on the seat before the ride starts, a rider is level and stationery, and the electronic sensor reads 770 n. at the top of the loop, the rider is upside down and moving, and the sensor reads 350 n.