If sound needs a medium to travel, how does the bell-jar experiment prove this requirement? What happens when air is removed, and why?
آواز کے سفر کو واسطہ درکار ہے؛ بیل جار کا تجربہ یہ کیسے ثابت کرتا ہے؟ ہوا نکالنے پر کیا ہوتا ہے اور کیوں؟
Solution & explanation
As air is removed, the ringing bell remains visibly vibrating but its sound becomes weaker because fewer gas particles transmit it. Residual sound may travel through the supports; this does not show sound crosses a vacuum.
Independent study answer. Original textbook ↗ · English-medium printed page 60–61.