Ashish Pathak

Masefield recalls the sight of the west lands and the old brown hills when viewed from his native hometown. Tears fell down when he reminds the memorable movements of west winds . He can feel the warm wind blowing from the west and carries with it the sounds that are full of birds’ songs. The vast area of apple orchards produces the fresh air with an aroma of wine. There is also a vast stretch of meadow that is covered with clean, cool and deep green grass. In the day time there are plenty of thrushes singing from their nests; whistling and singing with a clear, soft note like that of a flute. The west wind declares that it is the blossoming time of April and the white cleansing of May. The summer rain is soft and warm. It gives a wake-up call to him to come home from wherever he is . The bright sunny days are with some clouds in sky . The wild bees fly about with care-free hearts to see the merry spirit of spring again. The young corn has become green and everywhere around the field, the rabbits run in delight. Truly such a marvelous sight is like a song to any man’s soul . In the west lands above the green wheat, there are innumerable larks singing. The west wind carries with it the sound of music that is full of bird’s cries. Masefield assures all his friends a quiet rest for their tired feet, balms for bruised hearts and sleep for aching eyes. Masefield finally makes a resolute decision to return home westward and tread on the white road of truth. To reach his destination that is filled with the cool and green grass where he can rest his heart and head. The fine land that is filled with violets, warm hearts and thrushes songs is the west land where he belongs.

The deviation angle in a prism depends upon: Refractive index of the prism: The refractive index depends on the material and the wavelength of the light. The larger the refractive index, the larger the deviation angle. Angle of the prism: The larger the prism angle, the larger the deviation angle. Angle of incidence: The deviation angle depends on the angle that the beam enters the object, called angle of incidence. The deviation angle first decreases with increasing incidence angle, and then it increases. A convenient way to measure the refractive index of a prism is to direct a light ray through the prism so it produces the minimum deviation angle. This yields a simple formula:[2] n_\lambda={\sin ({A+D_\lambda \over 2}) \over \sin ({A \over 2})} where n is the refractive index at a wavelength ? , D is the angle of minimum deviation, and A is the internal angle of the prism. The angle of minimum deviation is attained when the angle of incidence and angle of emergence for a ray of light being refracted through a prism, are equal. It may be noted that minimum deviation in a rectangular slab is zero as both the surfaces separating two media are parallel, whereas, in a prism they are inclined to each other.A convenient way to measure the refractive index of a prism is to direct a light ray through the prism so it produces the minimum deviation angle. This yields a simple formula:[2] n_\lambda={\sin ({A+D_\lambda \over 2}) \over \sin ({A \over 2})} where n is the refractive index at a wavelength ? , D is the angle of minimum deviation, and A is the internal angle of the prism. The angle of minimum deviation is attained when the angle of incidence and angle of emergence for a ray of light being refracted through a prism, are equal. It may be noted that minimum deviation in a rectangular slab is zero as both the surfaces separating two media are parallel, whereas, in a prism they are inclined to each other.