Question

What are tides and how are they caused?

Answer 1

Hint:Ocean water is constantly in motion. The movements of the ocean are the consequence of many separate factors— wind, tides, Coriolis effect, water density differences, and the shape of the ocean basins.

Complete Answer:Tides are the periodic rise and fall of the sea level at any given place. The use of tide tables is common to determine the predicted times and amplitude of the tides at any given locales. They are caused by the combined effort of the sun and moon’s gravitational pull and rotation of the earth. The moon’s gravitational pull has a greater effect generating the tidal force because, although it is much smaller than the Sun, it is much closer to the earth. Another factor is centrifugal force, which acts to counterbalance the gravity. As the Moon revolves around the earth, its gravity pulls the earth towards it and mainly, the water is pulled by the gravity and a bulge is created. This bulge is the high tide created on the side of the earth facing the moon and its exact opposite side. Because water is pulled into the two high tides, low tides are formed between the two high tides. As the Earth rotates affected by the gravitational forces of the moon, a single location will experience two high tides and two low tides every day.

Note: The difference between the ocean level at high tide and the ocean at low tide is called the tidal range. Tides are used to generate energy and electricity in various parts of the world. In India, a 3 MW tidal power project at Durgaduani in Sunderbans, West Bengal is being set up.