Two spheres of equal masses but radii r1 and r2 are allowed to fall in a liquid of infinite column. The ratio of their terminal velocities is
1
r1 : r2
r2 : r1
A liquid flows through two capillary tubes A and B connected in series. The length and radius of B are twice those of A. What is the ratio of the pressure difference across A to that across B ?
n identical droplets are charged to V volt each. if they coalesce to form a single drop, then its potential will be
n2/3V
n1/3V
nV
V/n
A.
n2/3V
Let the radius of each droplet be r units. So, the volume of each droplet is equal to .
Thus, n droplets have the total volume equal to .
Since, the number of the drop would be equal to the total volume of the droplets hence,
⇒ R3 = nr3
⇒ R = n1/3r .... (i)
The capacitance of each droplet is equal to,
and thus the charge of each droplet would be equal to
.... (ii)
The capacitance of the bigger drop would be equal to
The potential of the bigger drop would be equal to V (say).
Hence,
A body floats in water with 40% of its volume outside water. When the same body floats in oil, 60% of its volume remains outside oil. The relative density of the oil is
0.9
1.2
1.5
1.8
A uniform long tube is bent into a circle of radius R and it lies in vertical plane. Two liquids of same volume but densities ρ and δ fill half the tube. The angle θ is
Two solid spheres of same metal but of mass M and 8M fall simultaneously on a viscous liquid and their terminal velocities are v and nv, then value of n is
16
8
4
2
A stone of relative density K is released from rest on the surface ofa lake. If viscous effects are ignored, the stone sinks in water with an acceleration of
g (1 − K)
g (1 + K)
An object weights m1 in a liquid of density d1 and that in liquid of density d2 is m2. The density d of the object is
A body floats in water with 40% of its volume outside water. When the same body floats in an oil. 60% of its volume remains outside oil. The relative density of oil is
0.9
1.0
1.2
1.5
Two soap bubbles of radii x and y coalesce to constitute a bubble of radius z. Then z is equal to
x + y