Surface Tension
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361211 Two soap bubbles have radii in the ratio of \(2: 1\). What is the ratio of excess pressures inside them?

1 \(1: 2\)
2 \(1: 4\)
3 \(2: 1\)
4 \(4: 1\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361212 The excess pressure inside a soap bubble is

1 Inversely proportional to the surface tension
2 Inversely proportional to its radius
3 Directly proportional to square of its radius
4 Directly proportional to its radius
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361213 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) kept in atmosphere are combined isothermally to form a big bubble of radius \(R\). The expression for surface tension will be

1 \(\dfrac{P_{o}\left(R^{3}+R_{1}^{3}+R_{2}^{3}\right)}{4\left(R^{2}+R_{1}^{2}+R_{2}^{2}\right)}\)
2 \(\dfrac{P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)}{4\left(R^{2}-R_{1}^{2}-R_{2}^{2}\right)}\)
3 \(P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
4 \(4 P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361214 Assertion :
Tiny drops of liquid resist deforming forces better than bigger drops.
Reason :
Excess pressure inside a drop is directly proportional to surface tension and inversely to radius.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361215 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) are in atmosphere of pressure \(P_{0}\) at constant temperature. Ratio of masses of air inside them is

1 \(\dfrac{\left(P_{o}+\dfrac{2 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{2 T}{R_{2}}\right) R_{2}^{3}}\)
2 \(\dfrac{\left(P_{o}+\dfrac{4 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{4 T}{R_{2}}\right) R_{2}^{3}}\)
3 \(\frac{{R_1^3}}{{R_2^3}}\)
4 \(\frac{{R_1^2}}{{R_2^2}}\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361211 Two soap bubbles have radii in the ratio of \(2: 1\). What is the ratio of excess pressures inside them?

1 \(1: 2\)
2 \(1: 4\)
3 \(2: 1\)
4 \(4: 1\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361212 The excess pressure inside a soap bubble is

1 Inversely proportional to the surface tension
2 Inversely proportional to its radius
3 Directly proportional to square of its radius
4 Directly proportional to its radius
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361213 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) kept in atmosphere are combined isothermally to form a big bubble of radius \(R\). The expression for surface tension will be

1 \(\dfrac{P_{o}\left(R^{3}+R_{1}^{3}+R_{2}^{3}\right)}{4\left(R^{2}+R_{1}^{2}+R_{2}^{2}\right)}\)
2 \(\dfrac{P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)}{4\left(R^{2}-R_{1}^{2}-R_{2}^{2}\right)}\)
3 \(P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
4 \(4 P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361214 Assertion :
Tiny drops of liquid resist deforming forces better than bigger drops.
Reason :
Excess pressure inside a drop is directly proportional to surface tension and inversely to radius.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361215 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) are in atmosphere of pressure \(P_{0}\) at constant temperature. Ratio of masses of air inside them is

1 \(\dfrac{\left(P_{o}+\dfrac{2 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{2 T}{R_{2}}\right) R_{2}^{3}}\)
2 \(\dfrac{\left(P_{o}+\dfrac{4 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{4 T}{R_{2}}\right) R_{2}^{3}}\)
3 \(\frac{{R_1^3}}{{R_2^3}}\)
4 \(\frac{{R_1^2}}{{R_2^2}}\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361211 Two soap bubbles have radii in the ratio of \(2: 1\). What is the ratio of excess pressures inside them?

1 \(1: 2\)
2 \(1: 4\)
3 \(2: 1\)
4 \(4: 1\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361212 The excess pressure inside a soap bubble is

1 Inversely proportional to the surface tension
2 Inversely proportional to its radius
3 Directly proportional to square of its radius
4 Directly proportional to its radius
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361213 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) kept in atmosphere are combined isothermally to form a big bubble of radius \(R\). The expression for surface tension will be

1 \(\dfrac{P_{o}\left(R^{3}+R_{1}^{3}+R_{2}^{3}\right)}{4\left(R^{2}+R_{1}^{2}+R_{2}^{2}\right)}\)
2 \(\dfrac{P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)}{4\left(R^{2}-R_{1}^{2}-R_{2}^{2}\right)}\)
3 \(P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
4 \(4 P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361214 Assertion :
Tiny drops of liquid resist deforming forces better than bigger drops.
Reason :
Excess pressure inside a drop is directly proportional to surface tension and inversely to radius.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361215 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) are in atmosphere of pressure \(P_{0}\) at constant temperature. Ratio of masses of air inside them is

1 \(\dfrac{\left(P_{o}+\dfrac{2 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{2 T}{R_{2}}\right) R_{2}^{3}}\)
2 \(\dfrac{\left(P_{o}+\dfrac{4 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{4 T}{R_{2}}\right) R_{2}^{3}}\)
3 \(\frac{{R_1^3}}{{R_2^3}}\)
4 \(\frac{{R_1^2}}{{R_2^2}}\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361211 Two soap bubbles have radii in the ratio of \(2: 1\). What is the ratio of excess pressures inside them?

1 \(1: 2\)
2 \(1: 4\)
3 \(2: 1\)
4 \(4: 1\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361212 The excess pressure inside a soap bubble is

1 Inversely proportional to the surface tension
2 Inversely proportional to its radius
3 Directly proportional to square of its radius
4 Directly proportional to its radius
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361213 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) kept in atmosphere are combined isothermally to form a big bubble of radius \(R\). The expression for surface tension will be

1 \(\dfrac{P_{o}\left(R^{3}+R_{1}^{3}+R_{2}^{3}\right)}{4\left(R^{2}+R_{1}^{2}+R_{2}^{2}\right)}\)
2 \(\dfrac{P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)}{4\left(R^{2}-R_{1}^{2}-R_{2}^{2}\right)}\)
3 \(P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
4 \(4 P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361214 Assertion :
Tiny drops of liquid resist deforming forces better than bigger drops.
Reason :
Excess pressure inside a drop is directly proportional to surface tension and inversely to radius.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361215 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) are in atmosphere of pressure \(P_{0}\) at constant temperature. Ratio of masses of air inside them is

1 \(\dfrac{\left(P_{o}+\dfrac{2 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{2 T}{R_{2}}\right) R_{2}^{3}}\)
2 \(\dfrac{\left(P_{o}+\dfrac{4 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{4 T}{R_{2}}\right) R_{2}^{3}}\)
3 \(\frac{{R_1^3}}{{R_2^3}}\)
4 \(\frac{{R_1^2}}{{R_2^2}}\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361211 Two soap bubbles have radii in the ratio of \(2: 1\). What is the ratio of excess pressures inside them?

1 \(1: 2\)
2 \(1: 4\)
3 \(2: 1\)
4 \(4: 1\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361212 The excess pressure inside a soap bubble is

1 Inversely proportional to the surface tension
2 Inversely proportional to its radius
3 Directly proportional to square of its radius
4 Directly proportional to its radius
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361213 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) kept in atmosphere are combined isothermally to form a big bubble of radius \(R\). The expression for surface tension will be

1 \(\dfrac{P_{o}\left(R^{3}+R_{1}^{3}+R_{2}^{3}\right)}{4\left(R^{2}+R_{1}^{2}+R_{2}^{2}\right)}\)
2 \(\dfrac{P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)}{4\left(R^{2}-R_{1}^{2}-R_{2}^{2}\right)}\)
3 \(P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
4 \(4 P_{o}\left(R_{1}^{3}+R_{2}^{3}-R^{3}\right)\)
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361214 Assertion :
Tiny drops of liquid resist deforming forces better than bigger drops.
Reason :
Excess pressure inside a drop is directly proportional to surface tension and inversely to radius.

1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
PHXI10:MECHANICAL PROPERTIES OF FLUIDS

361215 Two soap bubbles of radii \(R_{1}\) and \(R_{2}\) are in atmosphere of pressure \(P_{0}\) at constant temperature. Ratio of masses of air inside them is

1 \(\dfrac{\left(P_{o}+\dfrac{2 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{2 T}{R_{2}}\right) R_{2}^{3}}\)
2 \(\dfrac{\left(P_{o}+\dfrac{4 T}{R_{1}}\right) R_{1}^{3}}{\left(P_{o}+\dfrac{4 T}{R_{2}}\right) R_{2}^{3}}\)
3 \(\frac{{R_1^3}}{{R_2^3}}\)
4 \(\frac{{R_1^2}}{{R_2^2}}\)