Final answer:
The net force required to keep the car moving in the circular curve is 11111.25 Newtons.
Step-by-step explanation:
The force required to maintain a car moving in a circular curve is the centripetal force, which is directed towards the center of the curve. To calculate the centripetal force, we can use the formula:
Fc = (m * v2) / r
where Fc is the centripetal force, m is the mass of the car, v is the velocity, and r is the radius of the curve.
Substituting the given values:
Fc = (900 kg * (50 km/h)^2) / 40 m
Converting 50 km/h to m/s (1 km/h = 0.2778 m/s):
Fc = (900 kg * (13.89 m/s)^2) / 40 m
Simplifying the expression:
Fc = 11111.25 N
Therefore, the net force required to keep the car moving in the circular curve is 11111.25 Newtons.