Answer: b) The velocity vector is perpendicular to the acceleration vector; the acceleration vector is parallel to the net force vector.
Explanation: A change in velocity creates an acceleration. As the object rotates through the circular path it is constantly changing direction, and hence accelerating, which causes a constant force to act upon the object. This Force acts towards the center of curvature, directly toward the axis of rotation in a direction parallel to the acceleration of the body along the path. Because the object is moving perpendicular to the force, the path followed by the object is a circular one. Hence the velocity of the object is perpendicular to the acceleration.
You don't convert kilograms to newtons. By the time you've heard of these units, you know that 'kilogram' is a unit of mass, 'newton' is a unit of force or weight, and that mass and weight are different things.
Mass and force are <u>related</u> by Newton's second law:
Force = Mass x acceleration .
From this simple formula, you can see that in order to relate a mass to a force, you need to know an acceleration. And if the acceleration changes, then the relationship between the force and the mass also changes. So there's no direct conversion.
ON EARTH ONLY, one kilogram of mass <em>weighs</em> 9.8 newtons. The acceleration that connects them is the acceleration of gravity on Earth. In other places, with different gravitational accelerations, 1 kilogram weighs more or less newtons.
But they don't convert directly. That would be like asking "How do you convert miles to miles-per-hour ?"
Answer:
The answer is "Choice C ".
Explanation:
The relationship between the E and V can be defined as follows:

Let,

When E=0

v is a constant value
Therefore, In the electric potential in a region is a constant value then the electric-field must be into zero that is everywhere in the given region, that's why in this question the "choice c" is correct.
Decide which components you wish to assess yourself. There is no set order in which you do this. you could, for an example assess one or two elements and skip the rest.