Question
Physics Question on mechanical properties of fluid
A soap bubble, having radius of 1mm, is blown from a detergent solution having a surface tension of 2.5×10−2N/m. The pressure inside the bubble equals at a point Z0 below the free surface of water in a container. Taking g=10m/s2, density of water =103kg/m3, the value of Z0 is:
A
1 cm
B
0.5 cm
C
100 cm
D
10 cm
Answer
1 cm
Explanation
Solution
Excess pressure = R4T , Gauge pressure =ρgZ0
P0+R4T=P0+ρqZ0
Z0=R×ρg4T
Z0=10−3×1000×104×2.5×10−2m
Z0=1cm