A small metal sphere of radius 'r' and density 'ρ' falls from rest in a viscous liquid of density 'σ' and coefficient of viscosity 'η'. Which expression represents the time 't' it takes for the sphere to attain one-half of its terminal velocity (neglecting buoyancy)?
(2ρr²ln2)/(9η)
(4ρr²ln2)/(9η)
(ρr²ln2)/(9η)
(2ρr²ln3)/(9η)
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the ball attains constant velocity after some time
the ball stops
the speed of ball will keep on increasing
None of the above
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The lead shot will fall with an acceleration equal to g at that place
The velocity of lead shot will decrease with time
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Area of cross-section
Height of the liquid
Density of the ball
Density of the liquid
A metal sphere falling through glycerin has a terminal velocity 'v'. If we heat the glycerin, thereby decreasing its viscosity, what will happen to the terminal velocity of the sphere?
It will decrease
It will increase
It will remain the same
It will initially increase, then decrease
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Density of the body
Velocity of the body
Viscosity of the fluid
Shape of the body
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Moving with higher velocity
Made of denser material
Having larger surface area
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A straight line with a positive slope.
A parabola opening upwards.
A graph showing an initial increase in velocity followed by a gradual leveling off to a constant value.
A graph showing a constant decrease in velocity.
Spherical ball of radius are falling in a viscous fluid of viscosity ɳ with a velocity . The retarding viscous force acting on the spherical ball is
directly proportional to but inversely proportional to
directly proportional to both radius and velocity
inversely proportional to both radius and velocity
inversely proportional to but directly proportional to velocity
On which of the following, the terminal velocity of a solid ball in a viscous fluid is independent?
Area of cross-section
Height of the liquid
Density of the ball
Density of the liquid
Spherical ball of radius are falling in a viscous fluid of viscosity ɳ with a velocity . The retarding viscous force acting on the spherical ball is
directly proportional to but inversely proportional to
directly proportional to both radius and velocity
inversely proportional to both radius and velocity
inversely proportional to but directly proportional to velocity
