## Question

A large block of ice 5 m thick has a vertical hole drilled through it floating in the middle of a lake. What is the minimum length of a rope required to scoop up a bucket full of water through the hole?

[*RD* of ice = 0.9]

### Solution

0.5 m

As ice is floating, .

Now If *A* is the cross-section of the block, *L* its thickness and out of *L*,* h*is inside water, *V* = *AL* and *V _{in}* =

*Ah*.

i.e., 4.5 m of ice will be submerged in water. So the level of water in the hole will be 5 – 4.5 = 0.5 m below the top of ice and hence the length of rope required to scoop up water is 0.5 m.

#### SIMILAR QUESTIONS

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[*RD* of Hg = 13.6 and Fe = 7.2]