We can only apply the L’Hospital’s rule if the direct substitution returns an indeterminate form, that means 0 over 0 or 

When the rectangular metal tank is filled to the top with an unknown liquid, as observer with eyes level with the top of the tank can just see the corner E; a ray that refracts towards the observer at the top surface of the liquid is shown. The refractive index of the liquid will be

Following figure shows the multiple reflections of a light ray along a glass corridor where the walls are either parallel or perpendicular to one another. If the angle of incidence at point P is 30°, what are the angles of reflection of the light ray at points Q, R, S and T respectively

Which of the following ray diagram show physically possible refraction

A water drop in air refractes the light ray as

A small fish 0.4 m below the surface of a lake, is viewed through a simple converging lens of focal length 3 m. The lens is kept at 0.2 m above the water surface such that fish lies on the optical axis of the lens. The image of the fish seen by observer will be at

In a thin spherical fish bowl of radius 10 cm filled with water of refractive index 4/3 there is a small fish at a distance of 4 cm from the centre C as shown in figure. Where will the image of fish appears, if seen from E

An object is placed at a point distant x from the focus of a convex lens and its image is formed at I as shown in the figure. The distances x, x' satisfy the relation

Three lenses are placed co-axially as shown in figure. Focal length's of lenses are given 30 cm, 10 cm and 5 cm respectively. If a parallel beam of light falling on lens , emerging as a convergent beam such that it converges at the focus of . Distance between and will be

for a gas is 5/3 An ideal gas at is compressed adiabatically to 8/27 of its original volume The rise in temperature of the gas is

A wire is stretched by 0.01 m by a certain force F Another wire of same material whose diameter and length are double to the original wire is stretched by the same force ? Then what will be its. elongation?

To keep constant time, watches are fitted with balance wheel made of.....

Consider the melting of 1g of ice at to water at at atmospheric pressure Then the change in internal energy of the system(density of ice is 920kg/m³

The mean and variance of the random variable X which follows the following distribution are respectively 

If X is a random variable with the following distribution  where p+q=1 then the variance of X is