Light Worksheet-5

Light Worksheet-5

31. What is the coloured part of eye called?

32. What is the working of iris?

33. Where the image is formed in eyes?

34. Which part of eyes sends the sensation felt?

35. How many kinds of nerve cells are there in eyes?

36. Which is responsible for bright light and colour in our eyes ?

37. Which is responsible for dim light in our eyes?

38. What is the distinct vision of normal eye?

39. Who invented the system of reading for blind man?

40. What is reflection?

41. What is incident ray?

42. What is reflected ray?

43. Define normal.

44. Define angle of incident.

45. Define angle of reflection.

46. Write the laws of reflection.

47. What is lateral inversion?

48. What do you mean by diffused or irregular reflection?

49. Define regular reflection.

50. What do you mean by multiple images?

Answer:

31. Iris.

32. Iris controls the amount of light entering  the eye.

33. At retina

34. Nerve cells

35. Two (cones and rods)

36. Cones

37. Rods

38. 25 cm

39. Braille

40. When rays of light returns at some angle by striking a smooth surface, this phenomenon is called reflection of light.

41. The light ray, which strikes any surface, is called the incident ray.

42. The ray that comes back from the surface after reflection is known as the reflect ray.

43. A perpendicular line on the mirror at the point where incident ray strike is called normal.

44. The angle between the normal and incident ray is called the angle of incident.

45. The angle between the normal and reflected ray is called angle of reflection.

46. There are two laws of reflection.

(i) Angle of incidence is equal to angle of reflection.

(ii) Incidence ray, reflected ray and normal at the point of incidence are all lie in the same plane.

47. When an image is formed by a mirror the left of the object appears on the right and the right appears on the left, this is known as lateral inversion.

48. When all the parallel rays reflected from a plane surface are not parallel, the reflection is known as diffused or irregular reflection.

49. When reflection from a smooth surface are parallel, is known as regular reflection.

50. When two mirrors are kept parallel to each other and an object is placed between them then numerous images are seen in these mirrors of the object.