Which of the following are correct statements about an optical telescope?(e) Two or more convex lenses are used in this telescope.(f) To enter minimum light objective lens is smaller.(g) After entering light rays first refraction and then reflection occurs.(h) Eye piece is smaller than objective lens.(A) e, h(B) e, f (C) f, h(D) f, g, h14. 0.5 kWh = .................... J(A)(B)(C)(D)Space for rough useRao IIT Academy Website : www.raoiit.com4Rao IIT Academy / Pre-Foundation / Homi Bhabha / Official Exam / 2018 / Std. 9th / QP

Which of the following statements is true?(a) A convex lens has 4 dioptre power having a focal length 0.25 m(b) A convex lens has –4 dioptre power having a focal length 0.25 m(c) A concave lens has 4 dioptre power having a focal length 0.25 m(d) A concave lens has –4 dioptre power having a focal length 0.25 m

4. The type of lens used as a magnifying glass(a)Concave lens(b) Convex lens(c)Concavo-convex lens(d) Convexo-concave lens

7. You are provided with a convex mirror, a concave mirror, aconvex lens and a concave lens. You can get an inverted imagefrom(a) both concave lens and convex lens.(b) both concave mirror and convex mirror.(c) both concave mirror and convex lens.(d) both convex mirror and concave lens

Consider the following statements about images formed by several optical instruments.(A) The images formed by plane mirrors are always virtual, upright and equal in height of the object.(B) The images formed by concave lenses are always virtual, upright and smaller than the object.(C) Images formed by convex lenses are either real or virtual as well as inverted or upright.

Which of the following will occur if a corrective lens is placed in front of an eye that is unable to form a clear image of a nearby object?A.The focal length will shift away from the eye's lens.B.The focal length will shift closer to the eye's lens.C.Spherical aberration will increase.D.Optical power will decrease.