Normal force on a roller coaster descending a 45° hill

[Dmitri10]

Homework Statement

A rollercoaster car and passengers have a combined mass of 1620 kgm, and they descend the first hill at an angle of 45o to the horizontal. With what force is the roller coaster pulled down the hill?

Homework Equations

The Attempt at a Solution

Vertical force = 1620 kg * 9.81 = 15892.2 N
With a triangle in mind: cos(45) = 15892.2 / x
x[cos(45)] = 15892.2
x = 22475 N

Is this correct?

 

[Delphi51]

mg is straight down. Part of that is straight into the track and part is along the track, mg*cos(45). The answer must be smaller than the whole 15892.