Question

Period of rotation of Mercury is how many days?
(A) $365$
(B) $59$
(C) $1$
(D) $256$

Answer 1

Hint: The period of the rotation of the solar system is the length of the time it takes that the object has to spin one rotation, for example the earth takes $24$ hours to rotate once around its own axis. Like that mercury also rotates but the period of the rotation is not the same for earth and mercury.

Complete step by step answer:
The period of the rotation is the one full rotation off the object which the planet revolves around its own axis. The main reason that the mercury rotates slowly is because it is very close to the sun, so the gravitational force of attraction of the sun is more on the mercury because the mercury is the first planet in the solar system and it is very close to the sun than the earth. The gravitational force of attraction of the suns holds the rotation of the mercury. This is the reason for the mercury for having the greater period of the rotation of the mercury.

The earth takes only $24$ hours to the one revolution of its axis. But the mercury takes around $58$ days $15$ hours $30$ minutes, so the mercury takes around $59$ days for the one period of the revolution. That means from the starting point it starts revolving after $59$ days, it will reach the same starting point. The period of the rotation of the mercury takes around $59$ times the period of the rotation of the earth.

Hence, the option (B) is the correct answer.

Note:But the mercury revolves the sun faster than the earth revolves the sun, because the mercury is very close to the sun so the radius of the revolution of the mercury around the sun is smaller than the radius of the revolution of the earth around the sun.