QBManager

Mechanical Properties of Fluids

142800 An elliptically shaped ring of dimensions shown in figure just touches the horizontal surface of a liquid of surface tension $S$ . The force required to pull the away from the liquid surface is

1

2 π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

2

π (a_{1} + b_{1} + a_{2} + b_{2}) S

3

π (\frac{a_{1} + a_{2}}{2} + \frac{b_{1} + b_{2}}{2}) S

4

\sqrt{2} π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

Explanation:

A Internal circumference of the
$ring = 2 π r_{1} = 2 π \sqrt{a_{1} b_{1}}$
External circumference of the ring $= 2 π r_{2} = 2 π \sqrt{a_{2} b_{2}}$ Hence, force required
$F = 2 π S \sqrt{a_{1} b_{1}} + 2 π S \sqrt{a_{2} b_{2}}$
$= 2 π S (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}})$

JCECE-2015

Mechanical Properties of Fluids

142801 Two glass plates are separated by water, if surface tension of water is 75 dynes/cm and area of each plate wetted by water is $8 {cm}^{2}$ and the distance between the plates is $0.12 mm$ , then the force applied to separate the two plates is

1

10^{2}

dyne

2

10^{4}

dyne

3

10^{5}

dyne

4

10^{6}

dyne

Explanation:

C Given,
Surface tension $(T) = 75$ dynes $/ cm$
Area of each plate $(A) = 8 {cm}^{2}$
Distance between the plate $(d) = 0.12 mm = 0.012 cm$
Pressure difference $(Δ P) = \frac{2 T}{d}$
Area $(A) = 8 {cm}^{2}$
Force $F$ required to separate the two plates
$F = Δ P \times A$
$= \frac{2 T}{d} \times A = \frac{2 \times 75 \times 8}{0.012} = 10^{5} dyne$

JCECE-2007

Mechanical Properties of Fluids

142802 Assertion: Surface tension of all lubricating oils and paints is kept high.
Reason: Due to high value of surface tension the fluids get damaged.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-05.2018(M)

Mechanical Properties of Fluids

142803 Assertion: A small iron needle sinks in water while a large iron ship floats.
Reason: The shape of iron needle is like a flat surface while the shape of a ship is that which makes it easier to float.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-26.05.2018(M)

Mechanical Properties of Fluids

142800 An elliptically shaped ring of dimensions shown in figure just touches the horizontal surface of a liquid of surface tension $S$ . The force required to pull the away from the liquid surface is

1

2 π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

2

π (a_{1} + b_{1} + a_{2} + b_{2}) S

3

π (\frac{a_{1} + a_{2}}{2} + \frac{b_{1} + b_{2}}{2}) S

4

\sqrt{2} π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

Explanation:

A Internal circumference of the
$ring = 2 π r_{1} = 2 π \sqrt{a_{1} b_{1}}$
External circumference of the ring $= 2 π r_{2} = 2 π \sqrt{a_{2} b_{2}}$ Hence, force required
$F = 2 π S \sqrt{a_{1} b_{1}} + 2 π S \sqrt{a_{2} b_{2}}$
$= 2 π S (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}})$

JCECE-2015

Mechanical Properties of Fluids

142801 Two glass plates are separated by water, if surface tension of water is 75 dynes/cm and area of each plate wetted by water is $8 {cm}^{2}$ and the distance between the plates is $0.12 mm$ , then the force applied to separate the two plates is

1

10^{2}

dyne

2

10^{4}

dyne

3

10^{5}

dyne

4

10^{6}

dyne

Explanation:

C Given,
Surface tension $(T) = 75$ dynes $/ cm$
Area of each plate $(A) = 8 {cm}^{2}$
Distance between the plate $(d) = 0.12 mm = 0.012 cm$
Pressure difference $(Δ P) = \frac{2 T}{d}$
Area $(A) = 8 {cm}^{2}$
Force $F$ required to separate the two plates
$F = Δ P \times A$
$= \frac{2 T}{d} \times A = \frac{2 \times 75 \times 8}{0.012} = 10^{5} dyne$

JCECE-2007

Mechanical Properties of Fluids

142802 Assertion: Surface tension of all lubricating oils and paints is kept high.
Reason: Due to high value of surface tension the fluids get damaged.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-05.2018(M)

Mechanical Properties of Fluids

142803 Assertion: A small iron needle sinks in water while a large iron ship floats.
Reason: The shape of iron needle is like a flat surface while the shape of a ship is that which makes it easier to float.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-26.05.2018(M)

Mechanical Properties of Fluids

142800 An elliptically shaped ring of dimensions shown in figure just touches the horizontal surface of a liquid of surface tension $S$ . The force required to pull the away from the liquid surface is

1

2 π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

2

π (a_{1} + b_{1} + a_{2} + b_{2}) S

3

π (\frac{a_{1} + a_{2}}{2} + \frac{b_{1} + b_{2}}{2}) S

4

\sqrt{2} π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

Explanation:

A Internal circumference of the
$ring = 2 π r_{1} = 2 π \sqrt{a_{1} b_{1}}$
External circumference of the ring $= 2 π r_{2} = 2 π \sqrt{a_{2} b_{2}}$ Hence, force required
$F = 2 π S \sqrt{a_{1} b_{1}} + 2 π S \sqrt{a_{2} b_{2}}$
$= 2 π S (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}})$

JCECE-2015

Mechanical Properties of Fluids

142801 Two glass plates are separated by water, if surface tension of water is 75 dynes/cm and area of each plate wetted by water is $8 {cm}^{2}$ and the distance between the plates is $0.12 mm$ , then the force applied to separate the two plates is

1

10^{2}

dyne

2

10^{4}

dyne

3

10^{5}

dyne

4

10^{6}

dyne

Explanation:

C Given,
Surface tension $(T) = 75$ dynes $/ cm$
Area of each plate $(A) = 8 {cm}^{2}$
Distance between the plate $(d) = 0.12 mm = 0.012 cm$
Pressure difference $(Δ P) = \frac{2 T}{d}$
Area $(A) = 8 {cm}^{2}$
Force $F$ required to separate the two plates
$F = Δ P \times A$
$= \frac{2 T}{d} \times A = \frac{2 \times 75 \times 8}{0.012} = 10^{5} dyne$

JCECE-2007

Mechanical Properties of Fluids

142802 Assertion: Surface tension of all lubricating oils and paints is kept high.
Reason: Due to high value of surface tension the fluids get damaged.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-05.2018(M)

Mechanical Properties of Fluids

142803 Assertion: A small iron needle sinks in water while a large iron ship floats.
Reason: The shape of iron needle is like a flat surface while the shape of a ship is that which makes it easier to float.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-26.05.2018(M)

Mechanical Properties of Fluids

142800 An elliptically shaped ring of dimensions shown in figure just touches the horizontal surface of a liquid of surface tension $S$ . The force required to pull the away from the liquid surface is

1

2 π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

2

π (a_{1} + b_{1} + a_{2} + b_{2}) S

3

π (\frac{a_{1} + a_{2}}{2} + \frac{b_{1} + b_{2}}{2}) S

4

\sqrt{2} π (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}}) S

Explanation:

A Internal circumference of the
$ring = 2 π r_{1} = 2 π \sqrt{a_{1} b_{1}}$
External circumference of the ring $= 2 π r_{2} = 2 π \sqrt{a_{2} b_{2}}$ Hence, force required
$F = 2 π S \sqrt{a_{1} b_{1}} + 2 π S \sqrt{a_{2} b_{2}}$
$= 2 π S (\sqrt{a_{1} b_{1}} + \sqrt{a_{2} b_{2}})$

JCECE-2015

Mechanical Properties of Fluids

142801 Two glass plates are separated by water, if surface tension of water is 75 dynes/cm and area of each plate wetted by water is $8 {cm}^{2}$ and the distance between the plates is $0.12 mm$ , then the force applied to separate the two plates is

1

10^{2}

dyne

2

10^{4}

dyne

3

10^{5}

dyne

4

10^{6}

dyne

Explanation:

C Given,
Surface tension $(T) = 75$ dynes $/ cm$
Area of each plate $(A) = 8 {cm}^{2}$
Distance between the plate $(d) = 0.12 mm = 0.012 cm$
Pressure difference $(Δ P) = \frac{2 T}{d}$
Area $(A) = 8 {cm}^{2}$
Force $F$ required to separate the two plates
$F = Δ P \times A$
$= \frac{2 T}{d} \times A = \frac{2 \times 75 \times 8}{0.012} = 10^{5} dyne$

JCECE-2007

Mechanical Properties of Fluids

142802 Assertion: Surface tension of all lubricating oils and paints is kept high.
Reason: Due to high value of surface tension the fluids get damaged.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-05.2018(M)

Mechanical Properties of Fluids

142803 Assertion: A small iron needle sinks in water while a large iron ship floats.
Reason: The shape of iron needle is like a flat surface while the shape of a ship is that which makes it easier to float.

1 If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3 If Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

AIIMS-26.05.2018(M)

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Explanation:

Question Bank Series

Explanation:

Explanation:

Explanation:

Explanation: