Two capillaries of lengths L and 2 L and of radii R and 2 R respectively are connected in series. The net rate of flow of fluid through them will (Given, rate of the flow through single capillary, ) be
A wooden block is taken to the bottom of a deep, calm lake of water and then released. It rises up with a
constant acceleration
decreasing acceleration
constant velocity
decreasing velocity
There is a small hole in a hollow sphere. The water enters in it when it is taken to a depth of 40 cm under water. The surface tension of water is The diameter of hole is :
14mm
A water drop of radius R is split into n drops each of radius r. If the surface tension of water be a, the energy required to split the drop is given by :
A closed compartment containing gas is moving with some acceleration in horizontal direction. Neglect effect of gravity. Then the pressure in the compartment is
same everywhere
lower in the front side
lower in the rear side
lower in the upper side
A drop of water of volume 0.05 cm3 is pressed between two glass plates, as a consequence of which spreads and occupies an area of 40 cm2 . If the surface tension of water is 70 dyne/cm, then the normal force required to separate out the two glass plates will be :
22.5 N
45.0 N
90.0N
450.0N
A man is sitting in a boat, which is floating on a pond. If the man drinks some water from the pond, the level of water in the pond
decreases
increases
remains unchanged
may increase or decrease depending on the weight of the man
Spherical balls of radius R are falling in a viscous fluid of viscosity η with a velocity v. The retarding viscous force acting on the spherical ball is
directly proportional to R but inversely proportional to v
directly proportional to both radius R and velocity v
inversely proportional to both radius R and velocity v
inversely proportional to radius R and directly proportional to velocity v.
If there were no gravity, which of the following will not be there for a fluid ?
Viscosity
Surface tension
Pressure
Archimedes' upward thrust
Water from a tap emerges vertically downwards with an initial speed of 1.0 ms-1 . The cross-sectional area of the tap is 10-4 m2. Assume that the pressure is constant throughout the stream of water, and that the flow is steady. The cross-sectional area of the stream 0.15 m below the tap is
5.0×10-4 m2
1.0×10-5 m2
5.0×10-5 m2
2.0×10-5 m2