Question

How much time does earth take
(a) to revolve once around the sun
(b) to complete one rotation around its own axis?

Answer 1

Hint: One complete rotation by earth is equal to one day on earth. Calculate the number of hours in a day and it gives us the information about the time for one complete rotation. Also, one complete revolution around the sun is equal to one year. Calculate the number of days in one year and you can find the time taken easily.

Complete answer:
One revolution around the sun by earth is equal to one complete year on earth. One year consists of $365$ days. Talking precisely, it takes $365.24$ days for the earth to revolve around the sun.
One rotation by earth on its own axis is equal to one complete day on earth. One complete day on earth is equal to 23 hours, 56 minutes, 4 seconds precisely. Therefore, the earth takes this much time to complete its one rotation around its own axis.

Additional Information:
The movement of earth on its own axis is called earth's rotation. The movement of earth around the sun is called a revolution. In rotation, the centre of earth will not change its position, whereas in revolution, the centre of earth changes its position around the sun continuously. Earth does rotation and revolution simultaneously. Our earth goes close to the sun each year at perihelion on third January and farthest to the sun on fourth July at aphelion.

Note:
Usually, we take one revolution as $365$ days but it's not true. This is the reason why we get a leap year for every four years. On a leap year, the month of February has twenty-nine days rather than twenty-eight days. A leap year is also known as an intercalary year or bissextile year which is known for having an extra day than normal years.