Physics · Class 10 CBSE
A student enters a dark movie theatre from bright sunlight. Initially, the student cannot see clearly, but after a few minutes, vision improves. Which part of the eye is mainly responsible for this adjustment?
An elderly person has difficulty reading a newspaper held close to the eyes but can see distant objects clearly. Which defect of vision is most likely responsible?
A beam of white light passes through a glass prism and forms a spectrum on a screen. Which property of light is demonstrated?
The sky appears blue during the day because:
During sunrise, the Sun appears reddish. What is the main reason?
A doctor prescribes bifocal lenses for a patient. Which condition is the patient most likely experiencing?
A student notices that stars appear to twinkle, but planets generally do not. Which explanation is correct?
If the ciliary muscles lose their ability to change the curvature of the eye lens, what will happen?
A rainbow is formed after rainfall when sunlight falls on tiny water droplets. Which sequence of phenomena is mainly responsible?
Why does danger signal lighting usually use red colour?
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Why is the eye referred to as an \"accommodating\" optical system?
2 marksExplain why the sky appears blue during the day but black to astronauts in space.
2 marksDifferentiate between myopia and presbyopia based on: - Cause - Corrective lens used
2 marksWhy do stars twinkle while planets usually appear steady?
2 marksWhy does white light split into seven colours when it passes through a prism?
2 marksDescribe the structure and working of the human eye. Include the functions of: - Cornea - Iris - Pupil - Eye lens - Retina - Optic nerve Explain how an image is formed on the retina.
5 marksExplain atmospheric refraction and scattering of light with suitable real-life examples. In your answer, include: - Twinkling of stars - Advanced sunrise and delayed sunset - Blue colour of the sky - Red colour of the Sun at sunrise and sunset
5 marksCase study: Riya was travelling to school early in the morning. She noticed that the Sun looked reddish during sunrise. Later in the day, she observed that the sky appeared blue. At night, she saw stars twinkling while the nearby planet Venus appeared steady. Answer the following questions: (a) Why does the Sun appear reddish during sunrise?
1 markCase study: Riya was travelling to school early in the morning. She noticed that the Sun looked reddish during sunrise. Later in the day, she observed that the sky appeared blue. At night, she saw stars twinkling while the nearby planet Venus appeared steady. Answer the following questions: (b) Why does the sky appear blue during the daytime?
1 markCase study: Riya was travelling to school early in the morning. She noticed that the Sun looked reddish during sunrise. Later in the day, she observed that the sky appeared blue. At night, she saw stars twinkling while the nearby planet Venus appeared steady. Answer the following questions: (c) Why do stars twinkle but planets usually do not?
1 markCase study: Riya was travelling to school early in the morning. She noticed that the Sun looked reddish during sunrise. Later in the day, she observed that the sky appeared blue. At night, she saw stars twinkling while the nearby planet Venus appeared steady. Answer the following questions: (d) Name the phenomenon responsible for the advanced sunrise and delayed sunset.
1 mark