Force on a Spring

A spring has a length of 40 cm at rest, we hang to its free extremity an empty bottle, its length becomes 42 cm, we fill the bottle by 1.5 liter, the final length of the spring is 50 cm.
What is the weight of the empty bottle? (p pure alcohol = 800 kg/ $m^3$ . Please explain your solution in details.

#Physics

Easy Math Editor

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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$