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प्रश्न
A body of volume 100 cm3 weighs 5 kgf in air. It is completely immersed in a liquid of density 1.8 × 103 kg m-3. Find:
- The upthrust due to liquid and
- The weight of the body in liquid.
उत्तर
Volume of body = V = 100 cm3
= 100 × 10-6
= 10-4m3
Weight in air W = 5 kgf
Density of liquid d = 1.8 × 103 kg/m3
(i) Upthrust due to liquid = Volume of the solid submerged × density 0
= 10-4 × 1.8 × 103 × g
= 0.18 gN
= 0.18 kgf
(ii) Weight of body in liquid = Weight of body in air - upthrust
= 5 kgf - 0.18 kgf
= 4.82 kgf
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