How Does the Normal Force Compare to the Car's Weight in a Circular Valley?

[courtney1121]

A car travels at a constant speed of 23 m/s through a small valley whose cross section is like a circule of radius 310 m. What is the magnitude of the normal force on the car, expressed as a multiple of the car's weight?

what does it mean by the cross section and how does it relate to the problem?

 

[QuantumCrash]

You can assume the valey is sort of a semi-cylinder and the car travels on the circular part of it.