physics
posted by heather .
A special electronic sensor is embedded in the seat of a car that takes riders around a circular looptheloop at an amusement park. The sensor measures the magnitude of the normal force that the seat exerts on a rider. The looptheloop ride is in the vertical plane and its radius is 16 m. Sitting on the seat before the ride starts, a rider is level and stationary, and the electronic sensor reads 960 N. At the top of the loop, the rider is upsidedown and moving, and the sensor reads 360 N. What is the speed of the rider at the top of the loop?

The difference between the weight of 960 N and 360 N is V^2/R, the centripetal acceleration.
600 = V^2/R
Solve for for V.
You have posted a lot of probloems here. I will only help that show some work of your own. I can't speak for other teachers. 
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