An object weighs 30N in air and 21N in water. The weight of the object when completely immersed in a liquid of relative density 1.4 is
- 25.2N
-
17.4N
- 12.6N
- 9.0N
The correct answer is: B
Explanation
Weight of water displaced = upthrust = 30 - 21 = 9N
Mass of water displaced = \(\frac{9}{10}\) = 0.9kg
Volume of object = 9 × 10\(^{-4}\)m\(^3\)
= (9 × 10\(^{-4}\)) (1.4 ×103)
= 1.26kg = 12N
30 - 12.6 = 17.4N
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