A 1300 kg car traveling at a steady speed of 15 m/s initially due northwest round a corner so that after 10s, it is traveling due northeast. What is the magnitude and direction of the net force that must be acting on the car at the instant it is traveling due north?

Answer 1

the car goes through a quarter of a circle in 10 s, at a speed of 15 m/s

so the circumference of the circle is
... 10 * 15 * 4 = 600 m
... the radius is ... 600 / 2π

the centripetal force (which causes the car to travel in a curved path) is
... m v^2 / r

when the car is traveling north, this force is directed east

is gravity part of the "net force"?