Answer:
- No, this doesn't mean the electric potential equals zero.
Explanation:
In electrostatics, the electric field 
is related to the gradient of the electric potential V with :
This means that for constant electric potential the electric field must be zero:
This is not the only case in which we would find an zero electric field, as, any scalar field with gradient zero will give an zero electric field. For example:
give an electric field of zero at point (0,0,0)
30 + 6 = 36
36/12 = 3
So, it would take it 3 hours to go 12 kms downstream.
Note that we added 30 and 6 because it was going downstream. If it was going upstream, then we would have had to subtract.
Answer:
See the explanation below
Explanation:
Student c's belief is fulfilled only for the movement of the earth with respect to the sun. But it has no validity or does not exist when it is necessary to explain other physical phenomena with respect to other satellites. For example, how would you explain the phases of the moon, if the Earth is located in the center of the Galaxy?, another serious question regarding the observations made by scientists millions of years ago, where they observed that the distances of the Earth from other planets were changing, with respect to time. If the Earth was in the center, all the planets and the sun would revolve around it preserving a constant distance (radius), at all times.
Other phenomena to explain would be the seasons on Earth, these are due to the axis of inclination of the Earth and the rotation of it around the sun.
