The tides whose height is 20 percent more than normal tide are called
spring tides
neap tides
apogean and perigean tides
daily and semi-diurnal tides
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC CAPF – 2018
Tides are influenced by the gravitational pull of the moon and the sun. The height of tides varies depending on the relative positions of the Earth, Moon, and Sun, as well as the Moon’s distance from Earth. Perigean tides occur when the moon is closest to the Earth (at perigee), resulting in stronger gravitational pull and consequently higher high tides and lower low tides than average. Apogean tides occur when the moon is farthest from the Earth (at apogee), resulting in weaker pull and lower high tides and higher low tides. The difference in tidal range between perigean and apogean tides can be significant, often cited around 20-40%. The phrasing “whose height is 20 percent more than normal tide” strongly suggests the influence of the Moon’s distance, pointing towards perigean tides, which are grouped with apogean tides in option C as distinct categories based on distance.
Tidal height variations are influenced by the alignment of the Earth, Moon, and Sun (causing spring and neap tides) and the Moon’s distance from Earth (causing perigean and apogean tides). Perigean tides are higher than average due to the Moon’s closer proximity.