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Minor Versionm

by Suhail Ahanger

Introduction

An inflated balloon, submerged in a bottle of water can be made to sink by adding minimal weight to it and applying pressure to bottle.

  1. Blow a small amount of air into the balloon (refer to the picture), knot it and tie it up with cotton thread (~10cm).
    • Blow a small amount of air into the balloon (refer to the picture), knot it and tie it up with cotton thread (~10cm).

    • Tie a nut to the other end of the cotton thread.

    • The air blown into the balloon should be just enough to allow the balloon to float when submerged in water with the weight.

    • You can check whether the balloon and nut floats or not in a mug of water.

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  2. Carefully insert the balloon and nut into the bottle through its mouth.
    • Carefully insert the balloon and nut into the bottle through its mouth.

    • Fill the bottle with water to the top.

    • Screw the bottle cap on tightly and you are ready to play!

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    • Press the bottle from outside and observe what happens to the balloon.

    • Apply and adjust the pressure that you press the bottle with to make the balloon-nut assembly stay suspended in the middle of the bottle.

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    • Ensure the bottle is filled to the brim with water

    • If the balloon does not go down after applying pressure, it needs more weight! Add one more nut or remove some air from the balloon.

    • If the balloon does not float, it needs more air!

    • Not applying enough pressure on the bottle.

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    • Instead of adding weights on the thread, put beads or marble(s) into the balloon and tie it up.

    • Try with bigger balloons and a bigger water bottle.

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    • Tie two nuts instead of one. Did you still manage to make it work?

    • What happens once the nut touches the bottom of the bottle? Does the balloon keep sinking? Why or why not?

    • Can you estimate the force you have applied to make the balloon sink? A good way would be to apply a similar force to a weighing scale and see how much it shows up on the reading!

    • Weigh the nut and also measure the volume of the inflated balloon. Now determine what volume the balloon would have to be reduced to for it to sink.

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Finish Line

Kailash NR

Member since: 05/02/2017

2,989 Reputation

67 Guides authored

One Comment

We need some observation questions....

Procheta Mallik - Reply

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