(i) What is meant by:
(A) Spherical aberration?
(B) Chromatic aberration?
(ii) How can spherical aberration be reduced/minimized? Suggest any one method.
(i) (A) The defect in the definition of image produced due to inability of the marginal and paraxial set of rays to come to focus at a single point after refraction through the lens is called spherical aberration.
(B) Defect of the lens by which it is unable to bring the rays of different colour to focus at a single point.
(ii) Spherical aberration can be minimized or reduced by using stop or aperture.
(i) Define Resolving Power of a simple astronomical telescope.
(ii) State one advantage of a reflecting telescope over refracting telescope.
ndeviated through a uniform electric field for intensity 5 x 104 Vm-1 and a uniform magnetic field
.
(i) Find the magnitude of magnetic flux density B of the magnetic field.
(ii) What is the direction of is towards right and
is vertically downwards in the plane of this paper?