WorksheetsHuman eye
Total questions: 20
Worksheet time: 27mins
In the following dia. showing dispersion of white light by a glass prism, the colours p and q respectively are :
Red and violet
violet and red
red and blue
orange and green
In human eye the part which allows light to enter into the eye is:
Retina
Pupil
Eye lens
Cornea
The phenomena of light involved in the formation of rainbow are :
Refraction, dispersion and scattering
refraction , reflection and dispersion
refraction , dispersion and internal reflection
reflection, dispersion and total internal reflection
The change in the focal length of an eye lens in human beings is caused by the action of
optic nerves
ciliary muscles
retina
cornea
Name the phenomenon of light due to which the path of beam of light becomes visible when it enters a smoke filled room through a small hole
scattering
tyndall effect
dispersion
total internal reflection
when a beam of white light passes through a region having very fine dust particle, the colour of light mainly scattered in that region
red
orange
blue
yellow
Which of the following statements about the retina is true?
A) It is the outermost layer of the eye.
B) It is responsible for detecting color and fine details.
C) It produces tears that lubricate the eye.
D) It controls the amount of light that enters the eye
Assertion: the sky looks dark for an astronaut.
Reason: in space , all colour light travel with the same speed and together give the effect of dark colour.
a) Both A and R are true, and R is the correct explanation of A.
b) Both A and R are true, and R is not the correct explanation of A.
c) A is true, but R is false.
d) A is false, but R is true.
Assertion: the sun light has to cover a larger distance when it is overhead.
Reason : the sun appears white at noon
a) Both A and R are true, and R is the correct explanation of A.
b) Both A and R are true, and R is not the correct explanation of A.
c) A is true, but R is false.
d) A is false, but R is true
A person can see clearly objects lying between 25 cm and 2m from his eye. His vision can be corrected by using spectacles of power what?
-0.5 D
0.5 D
-2 D
2D
What happens to the image distance in the eye when we increase the distance of an object from the eye?
image distance will not change
it will be doubled
it will reduced to half
none of these
The ability of eye lens to adjust it ............ with help of ............. is called accommodation.
focus , ciliary muscles
focal length , ciliary muscles
none
focus , eye lens
A person is unable to see clearly a poster fixed on a wall. He however sees it clearly when standing at a distance of about 1.5 m from the wall. identify the defect of vision
presbyopia
myopia
hypermetropia
none of these
Name the type of lens used to correct myopia defect
double concave
concave lens
convex leaves
all of thses
Name the role of the part of human eye responsible for adjusting power of accommodation
ciliary muscles
iris
pupil
lens
A person cannot see the objects distinctly, when place at a distance less than 50 cm calculate the power of the lens, he should be using to see the object placed at a distance of 25 cm from his eyes.
2D
-2D
-50 D
50 CM
Draw a ray diagram to show the refraction of light through a glass prism. Mark on it (a) angle of incidence (b) the angle of emergency (c) the angle of deviation. (d) angle of prism
1. A star appears slightly higher (above) than its actual position in the sky.
What is the Tyndall effect? Give its example .
1. A star sometimes appears brighter and some other times fainter. What is this effect called? State the reason for this effect.
