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Gravitation — Science STD 9 — Question

Rajasthan BoardEnglish MediumSTD 9ScienceGravitation3 Marks
Question
An object is suspended with a string which gets stretched. When the object is completely immersed in water, the extension of string decreases. Explain why it happens.
✓

Answer

It happens because of the buoyancy force. The buoyant force is continuously acting on that body immersed in the liquid and that buoyant force is in the up direction, so that's the reason.
Although when the object is in air, then also buoyant force is acting but its comparatively less than the buoyant force acting when its immersed in liquid.

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