A hollow sphere has a small hole in it. On lowering the sphere in a tank of water, it is observed that water enters into the hollow sphere at a depth of 40 cm below the surface. Surface tension of water is7 xx 10 ^(-2) N//m. The diameter of the hole is approximately:

A hollow sphere has a small hole in it. On lowering the sphere in a ta

1.	A hollow sphere has a small hole in it. On lowering the sphere in a tank of water, it is observed that water enters into the hollow sphere at a depth of 40 cm below the surface. Surface tension of water is7 xx 10 ^(-2) N//m. The diameter of the hole is approximately:
Answer» 0.21 MM 0.14 mm 0.07 mm 0.7 mm Solution :Force due to SURFACE TENSION balancing the force due to pressure, hence `1000xx10xx(40)/(100)=(2sigma)/(R)=(2xx7xx10^(-2))/(R)Rightarrow2R=0.07mm`

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A hollow sphere has a small hole in it. On lowering the sphere in a tank of water, it is observed that water enters into the hollow sphere at a depth of 40 cm below the surface. Surface tension of water is7 xx 10 ^(-2) N//m. The diameter of the hole is approximately:

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