Final answer:
To keep a car of mass 1000 kg moving around a circular track with a radius of 100m at a constant speed of 39.7 m/s, a centripetal force of 15.769 kilonewtons is required.
Step-by-step explanation:
The question asks about the size of the force needed to keep a 1000 kg car moving in a circle of 100 m radius at a constant speed of 39.7 m/s. This is an application of centripetal force in a uniform circular motion. To find the force, we use the formula for centripetal force F = m × v2 / r, where m is mass, v is velocity, and r is the radius of the circle.
Mass (m): 1000 kg
Velocity (v): 39.7 m/s
Radius (r): 100 m
Using the formula: F = 1000 kg × (39.7 m/s)2 / 100 m = 15769 N
Converting newtons to kilonewtons, we get F = 15.769 kN (since 1 kN = 1000 N).
Therefore, the size of the force required is 15.769 kilonewtons.