Answer:
D. is always perpendicular to the surface of the conductor
Explanation:
1) Answer is (D) option. Electric field just outside surface of charged conductor is normal to conductor at that point.
It can be explained on the basis of the fact that, Electric field inside conductor under static condition is zero. As a result potential difference between any two points with in conductor is zero. So whole of conductor is equipotential body.
Equipotential surface and Electric field lines always cut at 90 degrees to each other. Conductor being equipotential body, Electric field lines starting or terminating at conductor must be normal to surface. Hence electric field just outside conductor is perpendicular or normal to surface.
To solve this problem, let us consider that the Earth is the
origin, the initial reference point. Therefore the speed of rocket plus the
missile would be 0.8 C
Now after the rocket had moved away from Earth, it fired a missile
at a speed of 0.7 C. Now the reference made to this is relative to the rocket.
We have established that our initial reference point is the Earth, therefore
the real speed of the missile with reference to Earth is:
Speed of missile relative to Earth = 0.8 C + 0.7 C
Speed of missile relative to Earth = 1.5 C
Answer is:
<span>A</span>
B I think hope this helps
