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SAI INTERNATIONAL SCHOOL, BHUBANESWAR
COMPETENCY BASED WORKSHEET
CLASS X

CHAPTER – HUMAN EYE AND THE COLOURFUL WORLD

SL NO QUESTIONS MARKS
For question 1 to 3, two statements are given. One labelled Assertion (A) and the
other labelled Reason(R). Select the correct answer to these questions from the codes
(a) , (b), (c) and (d) as given below:
(a) Both A and R are true and R is the correct explanation of the assertion.
(b) Both A and R are true, but R is not the correct explanation of the assertion.
(c) A is true, but R is false.
(d) A is false, but R is true.
(e) A and R are false.
1. Assertion (A): For making danger signals and signs that are at a distance, a 1
colour with a longer wavelength is used.
Reason (R): Colours with longer wavelengths travel faster than the other
colours.
2. Assertion (A): A rainbow is always formed in the sky after a rain shower and 1
in the same direction as sun.
Reason (R): Water droplets act like tiny prisms.
3. Assertion (A): Sky appears blue in colour. 1
Reason (R): Blue colour in sunlight travelling through atmosphere undergoes
maximum scattering.
4. A person standing at point Y 1
is watching a car coming from
a point X to O as shown. The
table shows the variation in
the parts of eye while seeing
the car at X and O.

Which change in the person’s eye would likely to occur while watching the
car?
a) 1 and 3
b) 1 and 4
c) 2 and 3
d) 2 and 4
5. Why stars appear to twinkle at night? 1
a) because the light of stars travels in different medium
b) because the distance of star varies when earth rotates
c) because the star changes its position relative to earth
d) because the atmosphere reflects the light at different angles
6. What would the size of the image formed on the retina depend on? 1
a) Age of the person
b) Curvature of the lens