Question

a glass bulb is balanced by a brass weight in a sensitive beam balance if yes then covered by a bell jar with is that evacuated then

Answer 1

A- the bean will remain horizontal

Answer 2

The bulb goes down

Explanation

when the glass bulb is weighed by a brass weight in air both of them displaces air, but the glass bulb being of much larger volume displaces larger volume of the air. when the system is covered by a bell jar. which is then evacuated the upthrust due to displaced air will be absent and the glass bulb will weigh more. thus, pen with the bulb goes down.