i) To evacuate the bell jar OR
To pump air in and out of the bell jar
ii) The electric bell starts ringing but its sound as heard from outside the bell jar reduces in intensity and diminishes. This is because as the air is pumped out, the density of air in the bell jar reduces. As this continues a vacuum is created
in the bell jar which cannot transmit sound hence the sound get diminished
iii) - It is not possible to create vacuum in the bell jar
- Some sound is transmitted through the connecting wires and the walls of the bell jar.
Kavungya answered the question on October 30, 2019 at 12:35
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