A 60kg rider stands on a scale in a Ferris wheel that is turning counter-clockwise in a vertical circle of radius 10m. When the rider is at the lowest point, the scale reads 2.1×103N. Assuming negligible friction, what will the scale read when the rider reaches the highest point of the circle? (Use g=9.8ms−2.)
a) 5.9×102N
b) 9.2×102N
c) 0N
d) 2.5×102N