<u>Answer: The model is described by :</u>
The strength of the field increases as you get closer to Earth, as shown by the smaller spaces between the circles.
Explanation :
According to universal gravitational law, the force acting in the universe between two objects is given by :

It is clear that the gravitational force depends directly on the product of masses and inversely on the square of the distance between them.
The given image shows a model of the gravitational field around Earth. The arrows in the image show the direction of the force. Gravitational field depends on the position of objects.
As we move closer to the earth, the force increases and hence the field increase.
So, the correct option is (D) " The strength of the field increases as you get closer to Earth, as shown by the smaller spaces between the circles ".
Answer:
The velocity of the cart at the bottom of the ramp is 1.81m/s, and the acceleration would be 3.30m/s^2.
Explanation:
Assuming the initial velocity to be zero, we can obtain the velocity at the bottom of the ramp using the kinematics equations:

Dividing the second equation by the first one, we obtain:

And, since
, then:

It means that the velocity at the bottom of the ramp is 1.81m/s.
We could use this data, plus any of the two initial equations, to determine the acceleration:

So the acceleration is 3.30m/s^2.
To solve this problem it is necessary to apply the equations related to the conservation of momentum.
This definition can be expressed as

Where
= Mass of each object
= Initial Velocity of each object
= Final velocity
Rearranging the equation to find the final velocity we have,

Our values are given as

Replacing we have,


Therefore the final velocity is 6.5m/s