Q1. A convex lens of glass (n=1.5) has focal length 0.2m. The lens is immeresed in water of refractive index 1.33. The change in the power of convex lens is ........
(A) 3.72 D
(B) 4.62 D
(C) 6.44 D
(D) 1.86 D
Q2. For a prism of refractive index √3, the angle of minimum deviation is eqviation is equal to the angle of prism, then angle of the prism is ...............
(A) 60°
(B) 90°
(C) 45°
(D) 180°
Q3. A ray of light is incident normally on one of the faces of a solid prism of angle 30° and refractive index √2. The angle of minimum deviation is ...........
(A) 39°
(B) 42°
(C) 52°
(D) 15°
Q4. A concave mirror has a focal length 30 cm. The distance between the two position of the object for which image size is double of the object is.............
(A) 30cm
(B) 15cm
(C) -25cm
(D) -15cm
Q5. A concave lens forms the image of an object such that the distance between the object and the image is 10 cm
and the magnification produced is 1/4, the focal length of lens will be ........... cm
(A) -6.2
(B) -12.4
(C) -4.4
(D) -8.8
Q6. A prism of certain angle deviates the red and blue rays by 8√ and 12√ respectively. Another prism of the same prism angle deviates the red light at smalll angle and made of different materials. The dispersive power of the materials of the prisms are in the ratio.........................
(A) 5:6
(B) 9:11
(C) 6:5
(D) 11:9
Q7. The head light of a jeep are 1.2m apart. If the pupil of the eye of an observer has diameter of 2 mm and light of wavelenght 5836 A^{°} is used what should be the maximum distance of the jeep from the observer if two head lights are just seem to be separated apart ?
(A) 30.9km
(B) 33.4km
(C) 3.34km
(D)30.9km
Q8. Interference is possible in ...........
(A) light wave only
(B) both light and sound waves
(C) sound waves only
(D) none of these
Q9. Huygin's wave theory of light can not explain ............. phenomina