Power grid
All the poles and wires you see along the highway and in front of your house are called the electrical transmission and distribution system. Today, generating stations all across the country are connected to each other through the electrical system (sometimes called the "power grid").
Answer:
The normal force will be lower than the gravitational force acting on the car. Therefore the answer is N < mg, which is <em>option B</em>.
Explanation:
Over a round hill, the centripetal force acting toward the the radius of the hill supports the gravitational force (mg) of the car. This notion can be expressed mathematically as follows:
At the top of a round hill

At the foot of a round hill

Explanation:
Graph A matches description 4 because the car is coming back.
Graph B matches description 3 because the speed of the car is decreasing.
Graph C matches the description 2 because the car is traveling at a constant rate.
Graph D matches the description 1 because the car is stopped.