Question

When we look at the pole star, it appears stationary because:
(a) It is very far from earth as compared to other stars.
(b) It moves with much lesser speed than the other stars.
(c) It is pointing exactly in the south direction.
(d) It is pointing exactly in the north direction.

Answer 1

Hint:
An object appears stationary from every point on the rotating body when it coincides with the axis of rotation of that body. Otherwise, for points not appearing on-axis and for every other point on sphere angular distance changes with respect to a point lying exterior to a rotating system.

Complete answer:
Pole stars appear stationary from every point on the earth. This is because it lies on the line along the axis of rotation of the earth. The pole star lies above the earth in the north. As we look directly above us, we see the pole star and it appears stationary.

When we look at the pole star, it appears stationary because: (d) It is pointing exactly in the north direction.

Additional Information:
 It can also be argued, that since the axis of rotation is itself rotating at an angle. Then, how could it be possible? This is because earth rotates from west to east and pole stars rotate from east to west. Therefore, at any time the pole star is always aligned to the axis of rotation of the earth. Hence, it would always be stationary apparently as everything in the universe is moving in reality. There is no actual stationary point in the Universe.

Note:
The rotation axis of the earth isn’t exactly perpendicular to the orbit plane. It has inclination away from the vertical axis while it’s orbiting around the sun. Still, the pole star lies along the axis. It would be slightly clear from additional information. Rest information is out of the scope of the present study of stellar motion.