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CBSE Class 9 Answered

1.   piece of stone is tied at one end of a rubber string and holding from other end ,it is allowed to immerse partially then fully into water what difference of any, you will observe and why?
Asked by M.s.srinidhi21 | 04 Mar, 2015, 06:07: PM
answered-by-expert Expert Answer

Hi Srinidhi,

When the rubber string is hanging freely, you will observe that the string elongates to its maximum. 
When the string in partially immersed in water, you will see that there is a slight decrease in the elongation of the string. This is because it experiences an upward buoyant force due to which the apparent weight of the stone decreases and there is a slight decrease in its elongation.
When the string is fully immersed in water, there is more buoyant force then in the earlier case and the elongation of the string decreases further.


Answered by | 04 Mar, 2015, 06:28: PM

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