In mammalian eye, the 'fovea' is the centre of the visual field, where

The fovea of eye

The potential energy of gas molecules in a certain certral field depends on the distance r from the field's centre as u( r) = ar^ , where a is a positive constant. The gas temperature is T , the concentration of molecules at the centre of the field is n_0 Find : (a) the number of molecules located at the distances between r and r + dr from the centre of the field , (b) the most probable distance separating the molecules from the centre of the field , ( c) the fraction of molecules located in the spherical layer between r and r + dr , (d) how many times the concentration of molecules in the centre of the field will change if the temperature decreases eta times.

In mammalian eye, the power of accommodation is controlled by changing thickness of the lens, governed by

A circular coil of radius R carries a current i . The magnetic field at its centre is B . The distance from the centre on the axis of the coil where the magnetic field will be B//8 is

Show by the priciple of superpostion that is a cavity is removed from a uniformly chaged sphere the field inside the cavity is rhovec(a//3epsi_(0) where rho is the centre ofchnages and veca is the vector from the centre of the sphere to the centre of the cavity.

The magnetic field at the centre of square of side a is

Retina of mammalian eye is composed of