The Human Eye And Its Colourful World Class 10 Physics Assignment Pdf
Class 10 Physics students should refer to the following printable assignment in Pdf for The Human Eye And Its Colourful World in standard 10. This test paper with questions and answers for Grade 10 Physics will be very useful for exams and help you to score good marks
Class 10 Physics Assignment for The Human Eye And Its Colourful World
Question : Which of the following colors is least scattered by fog, dust of smoke?
(a) Violet
(b) Blue
(c) Red
(d) Yellow
Answer : C
Question : Which of the following statements is correct regarding the propagation of light of different colors of white light in air?
(a) Red light moves fastest.
(b) Blue light moves faster than green light.
(c) All the colors of the white light move with the same speed
(d) Yellow light moves with the mean speed as that of the red and the violet light.
Answer : C
Question : In the following diagram, the path of a ray of light passing through a glass prism is shown:
In this diagram the angle of incidence, the angle of emergence and the angle of deviation respectively are (select the correct option):
(a) X, R and T
(b) Y, Q and T
(c) X, Q and P
(d) Y, Q and P
Answer : D
Question : Twinkling of stars is due to atmospheric
(a) Ultraviolet radiations are absorbed in the atmosphere.
(b) refraction of light by different layers of varying refractive indices
(c) scattering of light by dust particles
(d) internal reflection of light by clouds.
Answer : B
Question : A student traces the path of a ray through a glass prism for four different values of angle of incidence. On analyzing the diagrams, he is likely to conclude that the emergent ray
(a) is always parallel to the incident ray.
(b) Is always perpendicular to the incident ray
(c) Is always parallel to the refracted ray
(d) Always bends at an angle to the direction of incident ray.
Answer : D
Very Short Answers
Question : Why is the sun visible to us 2 minutes before actual sunrise and 2 minutes after actual sunset?
Answer : We are able to see the sun 2 minutes before actual sunrise and 2 minutes after actual sunset because sunrays undergo atmospheric refraction as they travel from an optically rarer medium to an optically denser medium when they enter the earth’s atmosphere due to which they are refracted downwards and hence appear to be above the horizon.
i. Iris of an eye = diaphragm in a camera.
Question : What is colour blindness?
Answer : Colour-blindness is the inability to distinguish the differences between certain primary colours. This condition results from an absence of color-sensitive pigment in the cone cells of the retina, the nerve layer at the back of the eye.
Question : Why do stars appear higher than their actual position?
Answer : Stars appear higher than their actual position as starlight undergoes refraction continuously on entering earth’s atmosphere and bends towards the normal.
Question : On the basis of which observation did Newton conclude that sunlight is made up of seven colours?
Answer : The observation on the basis of which Newton concluded that sunlight is made up of seven colours was the emergence of white light from the other side of a second identical and inverted prism placed alongside first prism and through which all colours of the spectrum were passed.
Question : Why is the colour of the clear sky blue?
Answer : The blue colour of sky is due to the scattering of sunlight by the large number of molecules such as fine dust particles, gases, water vapour etc present in the earth’s atmosphere.
As the size of the scatterer is much smaller than the wavelength of light, light of smaller wavelength such as blue is scattered the most as compared to light of longer wavelength.
Short Answers
Question : Use scattering of light? phenomenon to explain why (A) the Sun appears reddish at sun-rise, and (B) the clear sky appears blue.
Answer : Scattering of light is the phenomenon of change in the direction of light on striking an obstacle like an atom, a molecule, dust particle, water droplet etc.
(A) At the time of sunrise, the sun is near the horizon due to which sunrays have to travel much larger part of the atmosphere. Most of the blue light is thus scattered away. The red colour having the longest wavelength is scattered the least and hence enters our eyes.
(B) The blue colour of sky is due to the scattering of light by the large number of molecules and fine dust particles present in the earth’s atmosphere which mostly scatter light of shorter wavelength such as blue as the size of the scatterer is much smaller than the wavelength of light.
Long Answers
Question : (a) Draw a labeled ray diagram to illustrate the dispersion of a narrow beam of white light when it passes through a glass prism.
(b) A star appears slightly higher (above) than its actual position in the sky. Illustrate it with the help of a labelled diagram.
Answer : (a)
(b) Light from a star is refracted as it leaves vacuum and enters the earth’s atmosphere. Air at higher altitudes is rarer and is denser nearer to the earth’s surface. Thus when light coming from the star comes down, the dense air bends the light more. Due to this refraction of star’s light, the star appears to be at a higher position.
Question : State the cause of dispersion of white light passing through a glass prism. How did Newton show that white light of Sun contains seven colors using two identical glass prisms? Draw a ray diagram to show the path of light when two identical glass prisms are arranged together in inverted position with respect to each other and a narrow beam of white light is allowed to fall obliquely on one of the focus of the first prism.
Answer : White light is a mixture of lights of seven colors, red, orange, yellow, green, blue, indigo and violet. The dispersion of white light occurs because colors of white light travel at different speeds through the glass prism. The amount of refraction depends on the speed of colored light in glass. When white light consisting of seven colors falls on a glass prism, each color in it is refracted by a different angle, with the result that seven colors are spread out to form a spectrum. The red light bends the least, while violet bends the most.
Newton’s experiment with two identical prisms:
* When a beam of white light is passed through a glass prism, a band of seven colors is formed on a white screen. This band of seven colors is called spectrum of white light.
* Newton showed that the seven colored lights of the spectrum can be recombined to give back white light.
* First he tried to split the colors of the spectrum of white light using a prism.
* He then placed a second identical prism in an inverted position with respect to the first prism. This allowed all the colors of the spectrum to pass through the second prism. He found a beam of white light emerging from the other side of the second prism.
Question : ‘The human eye is like a camera’. Justify the statement.
Question : The eye lens forms an inverted real image of the object on the retina. But we perceive objects as they are. How is it possible?
Question : We are not able to see objects clearly for some time when we enter from bright light to a room with dim light. After sometime, however, we are able to see things in the dim-lit room.Why is it so?
Question : A person is not able to read the book comfortably but is able to read the matter written at far-off distance.
Name the defect of vision he is suffering from.
What is the cause for this defect?
With the help of the ray diagram show that how can this defect be corrected.
Question : Why is a normal eye not able to see clearly the objects placed at 10 cm?
Question : What is hypermetropia? Draw ray diagrams to show the image formation of an object by:
{i} Hypermetropic eye,
{ii} Correction made with a suitable lens for hypermetropic eye.
Question : The ciliary muscles of a normal eye are there in:
a) most relaxed
b) most contracted state
In which of the two cases is the focal length of the lens more. Explain.
Question : What is cataract? How is it corrected?
Question : The power of accommodation of the eye usually decreases with ageing. Why does it happen? How is it corrected?
Question : Which angle in a prism is known as the angle of the prism.
Question : Why do we see the seven colours when white light disperses? Which colour deviates the least?
Question : Trace the path of a ray of light passing through a glass prism and label it.
Question : A monochromatic beam of light does not split when it passes through a prism while a beam of White light does. How are the two cases different from each other? Explain.
Please click the below link to access CBSE Class 10 Physics The Human Eye And Its Colorful World Assignment
CBSE Class 10 Science Chemical Reactions and Equations Assignment Set A |
CBSE Class 10 Science Chemistry Chemical Reactions and Equations Assignment |
CBSE Class 10 Physics The Human Eye And Its Colorful World Assignment |
CBSE Class 10 Science Human Eye and Colorful World Assignment Set A |
CBSE Class 10 Science Human Eye and Colorful World Assignment Set B |
CBSE Class 10 Physics Magnetic Effects of Electric Current Assignment |
CBSE Class 10 Science Biology Our Environment Assignment |
CBSE Class 10 Science Our Environment Assignment Set A |
CBSE Class 10 Science Our Environment Assignment Set B |
CBSE Class 10 Science Chemistry Acids Bases and Salts Assignment |
CBSE Class 10 Science Acids Bases and Salts Assignment Set A |
CBSE Class 10 Science Acids Bases and Salts Assignment Set B |
CBSE Class 10 Science Metals and Non Metals Assignment Set B |
CBSE Class 10 Science Chemistry Metals and Non Metals Assignment |
CBSE Class 10 Science Carbon and its compounds Assignment Set A |
CBSE Class 10 Science Carbon and its compounds Assignment Set B |
CBSE Class 10 Science Biology How do Organisms Reproduce Assignment |
CBSE Class 10 Science How do Organisms Reproduce Assignment Set A |
CBSE Class 10 Science Assignment |
CBSE Class 10 Science Assignments Collection |
CBSE Class 10 Science Energy Crossword Puzzle Assignment |