When the temperature is increased, the angle of contact of a liquid
increases
decreases
remains the same
first increases and then decreases
The radii of two soap bubbles are R1 and R2 . If they coaleasce, the radius of curvature of the common surface will be :
R1 R2
R2 - R1
Radius of one arm of hydraulic lift is four times of radius of other arm. What force should be applied on narrow arm to lift 100 kg ?
26.5 N
62.5 N
6.25 N
8.3 N
A spherical drop of water has 1 mm radius. If the surface tension of water is 70 ×10-3 Nm-1, then difference of pressure between inside and outside of the spherical drop is
35 Nm-2
70 Nm-2
140 Nm-2
zero
An object is moving through the liquid. The viscous damping force acting on its is proportional to the velocity. Then dimensions of constant of proportionality are
[ ML-1 T--1 ]
[ MLT--1 ]
[ ML0 LT-1 ]
[ ML0 T--1 ]
A vessel contains oil (density = 0.8 g cm-3 ) over mercury (density = 13.6 g cm-3 ). A homogeneous sphere floats with half of its volume immersed in mercury and the other half in oil. The density of the material (in g cm-3 ) is
3.3
6.4
7.2
2.8
A wooden block, with a coin placed on its top, floats in water as shown in figure. The distance l and h are shown here. After some time the coin falls into the water. Then
l decreases and h increases
l increases and h decreases
both l and h increase
both l and h decrease
Work done to blow a bubble of volume V is W. The work done in blowing a bubble of volume 2V will be :
21/3 W
2W
41/3 W
4W
In old age arteries carrying blood in the human body become narrow resulting in an increase in the blood pressure. This follows from
Pascal's law
Stokes's law
Bernoulli's principle
Archimedes' principle
Drops of liquid of density are floating half immersed in a liquid of density . If the surface tension of the liquid is T, then the radius of drop will be :
