The Human Eye and Colourful World
What is the function of the cornea in the human eye?
Define the term 'power of accommodation' of the human eye.
What is myopia and how is it corrected?
Why do stars twinkle at night? Explain briefly.
Why does the clear sky appear blue during a sunny day?
What is dispersion of white light? Name the phenomenon.
Why do planets not twinkle at night?
What is the near point or least distance of distinct vision for a normal human eye?
What is the Tyndall effect? Give one example.
Explain the phenomenon of dispersion of white light through a glass prism. Draw a labelled diagram or describe the order of colours obtained.
A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type and focal length of the corrective lens used to restore proper vision?
Why does the clear sky appear blue during the day? Explain the underlying scientific principle in detail.
The near point of a hypermetropic person is 1 m. What is the power of the lens required to read a book clearly kept at 25 cm?
Why does the sun look reddish at sunrise and sunset? Explain the phenomenon and its scientific reason completely.
Calculate the power of a concave lens whose focal length is $-50\text{ cm}$. State the formula used and explain what the negative sign indicates.
A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of corrective lens used to restore proper vision? Also, calculate the power of the lens required.
Explain the structure and working of the human eye with the help of a labeled diagram. Also, explain the common defects of vision (myopia and hypermetropia) along with their corrective measures.
कांच के प्रिज्म से प्रकाश के अपवर्तन की परिघटना की विवेचना कीजिए। विचलन कोण को परिभाषित कीजिए तथा समझाइए कि प्रिज्म से गुजरने पर श्वेत प्रकाश अपने सात अवयवी रंगों में क्यों विभक्त हो जाता है, विक्षेपण का कारण बताइए।