When a rubber sucker is pressed onto a flat glass surface, it sticks tightly on the surface. Why ? You need a large force to separate it from the surface. Why ?

A drop of Volume V is pressed between the two glass plates so as to spread to an area of A . If T is the surface tension, the normal force required to separate the glass plates is

When a ray of light travels from air to glass slab and strikes the surface of separation at 90^(@) , then it

When a ray of light travels from air to glass and strikes the surface of separation at 90^@ ,then it

The force required to take away a flat circular plate of radius 4 cm from the surface of water is.

Consider a ray of light incident from air onto a slab of glass (reffractive index n) of width d , at an angle theta . The phase difference between the ray reflected by the top surface of the glass and the bottom surface is ,

The force of 2000 dyne is required to move a flat glass plate of surface area 10 cm^(2) with a velocity of 1 cm/s over a surface of glycerine 1 mm thick. The coefficient of viscosity of glycerine is

When a large bubble rises from the bottom of a lake to the surface its radius doubles. If atmospheric pressure is equal to that of column of water height H then the depth of lake is

A point object ‘O’ is placed on the axis of a cylindrical piece of glass of refractive index 1.6 as shown in the figure. One surface of the glass piece is convex with radius of curvature 3 mm. The point appeared to be at 5 mm on the axis when viewed along the axis and from right side of convex surface. The distance of the point object from the convex surface is

Answer the following questions: Take a large shining metal spoon. Bring the deeper(i.e., concave) surface closer to your face. Can you see your image? Now take the spoon away from your face. What change do you observe in the image? Now repeat the activity by turning the convex surface of the spoon to the front. What changes do you notice in the image?