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Wave Optics, Electromagnetic wave, Dual Nature and

Photoelectric effect, Ray Optica and Optical Instruments

Ionic Equilibrium Nitrogen Containing

Compound, Halogen Family and Inert Gas

Plant Growthand Development, Breathing & Gaseous

Transport, Body Fluid and Circulation

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TEST-1 SAMPLE PAPER for NEET(UG)-2020 1. The magnetic field of a beam emerging from a

filter facing a flood light is given by

B = 12 × 10–8 sin (1. 20 × 107 z – 3.60 × 1015 t) T. What is the average intensity of the beam ?

(a) 1.7 W/m2 (b) 2.3 W/m2ac

(c) 2.7 W/m2 (d) 3.2 W/m2

2. The ratio of contributions made by the electric field and magnetic field components to the intensity of an

(a) c : 1 (b) c2 : 1

(c) 1 : 1 (d) c :1

3. Assume that all the energy from a 1000 W lamp is radiated uniformly, then the amplitude of electric field of radiation at a distance of 2 m from the lamp is

(a) 245 .01 V/m (b) 17 V/m

(c) 0 (d) 2.96 V/m

4. A ray of light is incident on the surface of separation of a medium at an angle 45º and is refracted in the medium at an angle 30º. What will be the speed of light in the medium?

(a) 1.96 × 108 ms–1

(b) 2.12 × 108 ms–1

(c) 3. 18 × 108 ms–1

(d) 3.33 × 108 ms–1

5. A fish looking up through the water sees the outside world, contained in a circular horizon. If

the refractive index of water is 4 3

and the fish is

12 cm below the water surface, the radius of this circle in cm, is

(a) 36 7 (b) 36 7

(c) 36 5 (d) 4 5

6. Light is incident from a medium into air at two

possible angles of incidence (a) 20º and (b) 40º. In the medium, light travels 3.0 cm in 0.2 ns. the ray will

(a) suffer total internal reflection in both cases (a) and (b)

(b) suffer total internal reflection in case (b) only

(c) have partial reflection and partial transmission in case (b)

(d) have 100% transmission in case (a)

7. The image of an illuminated square is obtained on a screen with the help of a converging lens. The distance of the square from the lens is 40 cm. The area of the image is 9 times that square. The focal length of the lens is

(a) 36 cm (b) 27 cm

(c) 60 cm (d) 30 cm

8. A double convex lens made of glass (refractive index n = 1.5) has the radii of curvature of both the surfaces as 20 cm. Incident light rays parallel to the axis of the lens will converge at a distance L such that

(a) L = 20 cm (b) L = 10 cm

(c) L = 40 40 cm (d)

9. When monochromatic red light is used instead of blue light in a convex lens, its focal length will

(a) not depend on colour of light

(b) increase

(c) decrease

(d) remain same

10. To make an achromatic combination, a convex lens of focal length 42 cm having dispersive power of 0.14 is placed in contact with a concave lens of dispersive power 0.21. The focal length of the concave lens should be

(a) 63 cm (b) 21 cm

(c) 42 cm (d) 14 cm

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TEST-1 SAMPLE PAPER for NEET(UG)-2020 11. A convex lens is in contact with a concave lens.

The magnitude of the ratio of their focal length

is 3 2 . Their equivalent focal length is 30 cm. What

are their individual focal lengths

(a) –75, 50 (b) –10, 15

(c) 75, 50 (d) –15,10

12. An equiconvex lens is cut into two halves along (i) XOX' and (ii) along YOY' as shown in figure. Let f, f' and f" be the focal lengths of the complete lens, of each half in case (i), and of each half in case (ii) respectively. Choose the correct statement from the following

(a) f' = 2f, f" = f (b) f' = f, f" = f

(c) f' = 2f, f" = 2f (d) f' = f, f" = 2f

13. A small coin is resting on the bottom of a beaker filled with a liquid. A ray of light from the coin travels upto the surface of the liquid and moves along its surface (see figure).

How fast is the light travelling in the liquid

(a) 1.8 × 108 ms–1

(b) 2.5 × 108 ms–1

(c) 3.0 × 108 ms–1

(d) a1.2 × 108 cm–1

14. The reflective surface is given by y = 2 sin x and it is facing positive axis. What is the least value of coordinate of the point where a ray parallel to positive X-axis becomes parallel to positive y - axis after reflection

(a) (b)

(c) (d)

15. A light ray is incident perpendicular to one face of a 90º prism and is totally internally reflected at the glass-air interface. If the angle of reflection is 45º, we conclude that for the refractive index n as

(a) n (b)

(c) n (d)

16. Diameter of a plano-convex lens is 6 cm and thickness at the centre is 3 mm. If speed of light in material of lens is 2 × 108 m/s, the focal length of lens

(a) 15 cm (b) 20 cm

(c) 30 cm (d) 10 cm

17. A plano-convex lens of refractive index 1.5 and

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TEST-1 SAMPLE PAPER for NEET(UG)-2020 radius of curvature 30 cm is silvered at the curved surface. Now, this lens has been used to form the image of an object. At what distance from this lens, an object be placed in order to have a real image of the size of the object ?

(a) 20 cm (b) 30 cm

(c) 60 cm (d) 80 cm

18. A thin convex lens made from crown glass

has focal length f. When it is measured

in two different liquid having refractive indices

4 5 and

5 3 , if has focal lengths f1 and f2,

respectively. The correct relation between focal length is

(a) f2 > f and f1 becomes one

(b) f1 and f2 both becomes one

(c) f1 = f2 < f

(d) f1 > f and f2 becomes one

19. A light ray falls on a square glass salb as shown in the diagram. The index of refraction of the glass, if total internal reflection is to occur at the vertical face, is equal to

(a) 2

(b) 5 2

(c) 3 2 (d)

3 2

20. A car is fitted with a convex side-view mirror of focal length 20 cm. A second car 2.8 m behind the first car is overtaking the first car at a relative speed of 15 m/s. The speed of the image of the second car as seen in the

(a) 1 m/s

15 (b) 10 m/s

(c) 15 m/s (d) 1

m/s 10

21. A diverging lens with magnitude of focal length 25 cm is placed at a distance of 15 cm from a converging lens of magnitude of focal length 20 cm. A beam of parallel light falls on the diverging lens. The final image formed is

(a) virtual and at a distance of 40 cm from convergent lens

(b) real and at a distance of 40 cm from the divergent lens

(c) real and at a distance of 6 cm from the convergent lens

(d) real and at a distance of 40 cm from convergent lens

22. An object 2.4 m infront of a lens forms a sharp image n a film 12 cm behind the lens. A glass plate 1 cm thick, of refractive index 1.50 is interposed between lens and film with its plane faces parallel to film. At what distance (from lens) should object shifted to be in sharp focus on film ?

(a) 7.2 m (b) 2.4 m

(c) 3.2 m (d) 5.6 m

23. Two plane mirror A and B are aligned parallel to each other, as shown in the figure. A light ray is incident at an angle 30º at a point just inside one end of A. The plane of incidence coincides with the plane of the figure. The maximum number of times the ray undergoes reflection (including the first one) before it emerges out is

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TEST-1 SAMPLE PAPER for NEET(UG)-2020

(a) 28 (b) 30

(c) 32 (d) 34

24. A simple telescope, consisting of an objective of focal length 60 cm and a single eye lens of focal length 5 cm is focused on a distant object in such a way that parallel rays emerge from the eye lens. If the object subtends an angle of 2º at the objective, the angular width of the image is

(a) 10º (b) 24º

(c) 50º (d) (1/6)º

25. The magnifying power of an astronomical telescope is 8 and the distance between the two lenses is 54 cm. The focal length of eye lens and objective lens will be

(a) 6 cm and 48 cm (b) 48 cm and 6 cm

(c) 8 cm and 64 cm (d) 6 cm and 60 cm

26. In a refracting astronomical telescope, the final image is

(a) real, inverted and magnified

(b) real, erect and magnified

(c) virtual, erect and magnified

(d) virtual, inverted and magnified

27. An observer looks at a distance tree of height 10 m with a telescope of magnifying power of 20. To the observer the tree appears

(a) 10 times taller (b) 10 times nearer

(c) 20 times taller (d) 20 times nearer

28. For compound microscope f0 = 1 cm, fe = 2.5 cm. An object is placed at distance 1.2 cm from objective lens. What should be the length of microscope for normal adjustment ?

(a) 8.5 cm (b) 8.3 cm

(c) 6.5 cm (d) 6.3 cm

29. In a Young's double slit experiment, two coherent sources are placed 0.90 mm apart and the fringes are observed one metre away. If it produces the second dark fringe at a distance of 1 mm from the central fringe, the wavelength of monochromatic light used will be

(a) 60 × 10–4 cm (b) 10 × 10–4 cm

(c) 10 × 10–5 cm (d) 6 ×10–5 cm

30. In Young's double slit experiment, the intensity

at a point where the path difference is 6

being

the wavelength of the light used) is I. If I0 denotes the maximum intensity, I/I0 is equal to

(a) 1 2 (b)

3 2

(c) 1 2 (d)

3 4

31. In Young's double slit experiment, the intensity at a point