4. If the Earth were to spin half as fast as it does now, how many hours would be in one day (one complete spin)?
Answers
Explanation:
If the Earth routinely spun at half its speed, days and nights at the equator would be each 24-hours in length instead of just 12-hours. Depending on how far north or south of the equator you are things would be a little bit different (as they are now). While there would still take the same actual number of hours for Earth to go once around the Sun, the definition of a year, we might say it takes 182.6 “days” for the Earth to do so (since each day would be twice as long). I am hoping you are not asking what would happen to all the living creatures that are used to about 12-hours daylight and 12-hours darkness, nor what would happen were Earth to SUDDENLY to this (not likely, not possible, never going to happen, not all at once).
Let us compute the answer by the following calculation:
Given:
Speed of earth's rotation = 1/2 (current speed)
To find:
Time taken to complete 1 spin = ?
Step-wise explanation:
Current speed of Earth's rotation at the equator = 1670 Km/ h
If it rotates at half of its current speed then,
Speed = 1/2 × 1670 Km/h
= 835 Km/h
Circumference of the earth at equator = Distance travelled by earth in one complete spin = 40,000 Kms
Speed = Distance ÷ Time
∴ Time = Distance ÷ Speed
= 40,000 Km ÷ 835 Km/h
= 47.904 hours which is equivalent to 48 hours
- The entire day cycle will be of 48 hours instead of 24 hours.
- It will be divided as 24-24 cycle instead of 12-12 cycle of day and night.
- Hence, the Earth will take 48 hours to finish one complete spin if its speed is half of its present speed.