Answer:
A generator turns rotary motion into electricity. It is basically the inverse of a motor. Generally a transformer changes one voltage into another based on the number of conductor windings on each side. There are two sets of windings called the “primary” and the “secondary”.
Explanation:
Answer: Yes.
Explanation: It is clearly stated in Newton’s first law of physics that an object will not change its motion unless a force acts on.
Answer:
The slope of a position-time graph represents an object’s velocity.
Explanation:
In a position-time graph, the values on the x-axis represent the time, while the values on the y-axis represent the position of the object.
Velocity is defined as the ratio between the displacement of an object and the time taken:

However, we can see that this definition corresponds to the slope of the curve in a position-time graph. In fact:
, the displacement, corresponds to the difference in position, so the difference between the values on the y-axis: 
, the time interval, corresponds to the difference in times, so the difference between the values on the x-axis: 
So, the velocity is

which corresponds to the slope of the curve.
The question is poor. Light doesn't refract on its way THROUGH anything. It refracts at the boundary BETWEEN two different media. The effect is greatest where the ratio of the speeds of light in the two media is greatest. On your list, that would be at the boundary between air or space and glass.
C: if it senses unequal currents