Oceanography : Movements Of Ocean

Q 3 / 11

UPSC CSE Prelims 2015

Tides occur in the oceans and seas due to which among the following?

  1. Gravitational force of the Sun
  2. Gravitational force of the Moon
  3. Centrifugal force of the Earth
Select the correct answer using the code given below.

EXPLANATION

Correct Option (d)

Tides are a complex phenomenon resulting from the combined influence of multiple forces:

  • Gravitational force of the Moon: The Moon's gravitational pull is the primary driver of tides. It creates a bulge of water on the side of the Earth facing the Moon.
  • Gravitational force of the Sun: Although less significant than the Moon's gravitational force due to its greater distance, the Sun's gravity also contributes to tidal forces. When the Sun, Moon, and Earth align (during new and full moons), their combined gravitational pull results in higher 'spring tides'.
  • Centrifugal force of the Earth-Moon system: As the Earth and Moon revolve around their common center of mass, a centrifugal force is generated. This force acts equally on all parts of the Earth, pushing water away from the Moon on the side opposite to it, creating a second tidal bulge.

Incorrect Options

Options (a), (b), and (c) are incomplete as they do not account for all the fundamental forces responsible for the generation of tides. Tidal phenomena are a result of the synergistic interaction of the gravitational forces of both the Sun and the Moon, along with the centrifugal force generated by the Earth-Moon system's revolution. Excluding any of these forces provides an incomplete explanation of tidal formation.

SOURCECertificate Physical and Human Geography by G.C. Leong, Chapter 14: Oceans