When we press the bulb of a dropper with its nozzle inside water, the air present in the bulb escapes in form of bubbles. Once we release pressure on the bulb, water gets filled in the dropper. The rise of water in the dropper is driven by_________.
A
pressure difference
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
pressure inside the dropper
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
shape of rubber bulb
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
gravity of Earth
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A pressure difference When we press the bulb of a dropper, the number of air molecules decreases which results in a decrease in pressure inside the dropper nozzle. However, the outside pressure or atmospheric pressure remains the same. Therefore there is a difference in pressure between outside of the nozzle and inside of the nozzle. Since water flows from a region of higher pressure to a region of lower pressure, water rushes to fill inside the dropper.