The correct option is 2 only.
Explanation
Tides are the periodic rise and fall of sea levels caused by the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth. Based on the frequency of occurrence within 24 hours, tides are classified into three main types: semi-diurnal, diurnal, and mixed.
Statement-wise Analysis:
- Statement 1 is Incorrect.
A semi-diurnal tide is the most common tidal pattern, featuring two high tides and two low tides each day. The successive high or low tides are approximately of the same height.
- Statement 2 is Correct.
A diurnal tide features only one high tide and one low tide during each day. The successive high and low tides are approximately of the same height.
- Statement 3 is Incorrect.
Mixed tides are characterized by variations in height between successive high and low tides. These generally occur along the west coast of North America and on many islands of the Pacific Ocean. The east coast of North America typically experiences semi-diurnal tides.
Key Takeaway:
Diurnal tides have one high and one low tide per day; semi-diurnal tides have two high and two low tides per day; and mixed tides show significant height variations, commonly found on the North American west coast.