Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q42 (CDS-II/2008) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Basic mechanics concepts Answer Verified

Assertion (A) : It is easier to swim in sea- water compared to ordinary water. Reason (R) : Density of sea-water is higher than that of ordinary water.

Result
Your answer: —  Â·  Correct: A
Explanation

The assertion that swimming in sea water is easier than in ordinary (fresh) water is true. This phenomenon is explained by the higher density of sea water compared to fresh water [t1][t2]. Sea water contains dissolved salts, which increase its mass per unit volume [t6][t8]. According to Archimedes' principle, the upward buoyant force exerted on an object is equal to the weight of the fluid it displaces [t9]. Because sea water is denser, a swimmer displaces a weight of water equal to their own body weight while submerging less of their volume compared to fresh water [t3][t5]. This increased buoyancy makes it easier to stay afloat and swim [t1][t7]. Therefore, the reason provided correctly explains why the assertion is true, as the higher density directly results in the greater buoyant force that facilitates easier swimming.

Sources

  1. [1] https://www.noaa.gov/ocean/ll-eggs
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
79%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

CDS-I · 2002 · Q38 Relevance score: 4.21

Assertion(A): Sea water is warmer than that of ofcean. Reason (R): Ocean receives more admixture of water from outside through the ocean currents.

CDS-I · 2007 · Q4 Relevance score: 3.20

Assertion (A) : In winter, although many lakes and rivers are frozen, the marine fish still survives. Reason (R) : The density of water is maximum at 4°C. Hence, water below the frozen outer surface is maintained at 4°C.

CDS-I · 2009 · Q93 Relevance score: 3.12

Assertion (A) : Despite low evaporation and stable stratification of the atmosphere, salinity is high in polar regions. Reason (R) : Sea water freezes leaving the remaining water saline than before.

CDS-I · 2006 · Q52 Relevance score: 2.99

Assertion (A): The salinity of oceans is relatively higher near the equator than at other regions. Reason (R): Equator region has heavy rainfall, high relative humidity and calm air.

CDS-I · 2009 · Q92 Relevance score: 2.09

Assertion (A) : Physiological density is preferable to arithmetic density as an index of population density. Reason (R) : Physiological density is based on arable land while arithmetic density is based on total area.