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We always see the same face of the moon, because
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- it is smaller than the earth
- it revolves on its axis in adirection opposite to that ofthe earth
- it takes equal time for revolution around the earth and rotation on its own axis
- it rotates at the same speed as the earth around the sun
- it is smaller than the earth
Correct Option: C
It is tidal locking that causes the synchronous rotation which causes the Moon to present “just one side” to the Earth all the time. The Moon rotates (spins) but very slowly, making one turn on its axis in the same time it takes to revolve (orbit) around the Earth. So it maintains a “constant face” in our direction. We actually see slightly more than half of its surface as it turns. Tidal locking (or captured rotation) occurs when the gravitational gradient makes one side of an astronomical body always face another, an effect known as synchronous rotation. For example, the same side of the Earth’s Moon always faces the Earth. A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This causes one hemisphere constantly to face the partner body.
