REFRACTION OF LIGHT AND OPTICAL INSTRUMENTS
IMPORTANT QUESTIONS OF PAST PAPERS:
1)Define(i)Total Internal Reflection (2010)
(ii) Refractive Index (2010)
(iii) Critical Angle (2010)
(iv) Power of a lens (2010, 2016)
(v) Magnifying Glass (2010)
(vi)(2011)
2)Draw the (neat and ) labelled diagram of compound Microscope and write (describe) its working. (2008, 2011, 2013, 2016) OR
3) State Snell’s law? (2011, 2016)
4) Draw the neat and labelled diagram of simple Microscope. write down the characteristic of image formed by it and the formula of its magnifying power. (2012)
5) Draw ray diagram of compound microscope describe its working? (2013)
6) With the help of prism, Draw solar spectrum of dispersion of light? (2014)
7) Draw the diagram of defects of eyes. Describe short and long sightedness. ( 2014) OR
◾ With the help of diagram show and explain short sightedness amd long sightedness and its correction.(2015)
8) With the help of Snell's law prove that there is no change in direction of refracted ray if the incident ray is perpendicular on the surface separating the two media. (2015)
9) Draw a ray diagram of an Astronomical Telescope and describe its working.( 2017)
10) Name two main defects of Human Eye. Describe with the help of ray diagrams show the defects and their corrections. (2019)
Numerical:
1) A convex lens forms a virtual image of an object placed 5 cm away from the optical center at a distance of 10 cm. Determine the focal length of the convex- lens. (2010) OR
◾ Find the focal length of a convex lens. If P = 5cm, q = 10 cm and the image formed is virtual.(2011, 2013) ( Hint: Formula ; 1/f = 1/p + 1/q)
2) Find the Focal length of a concave lens. If P =5 cm, q = 10 cm and the image formed is virtual. (2011) ( Hint: Formula ; 1/f = 1/p + 1/q)
3) The focal length of a convex lens is 20 cm. If the image formed by it is twice in size. Find the position of the object. (2014) ( Hint: q= 2p, Formula ; 1/f = 1/p + 1/q)
4) An object is placed 10 cm from a convex lens of focal length 15 cm . Find the position and magnification of a image. (2015) ( Hint:Formula ; 1/f = 1/p + 1/q and magnification = p/q )
5) Calculate the distance of object from a convex lens having a focal length of 15 cm if the magnification is 3 and the image is real. (2017) ( Hint:Formula ; 1/f = 1/p + 1/q )
6) The focal length of a convex lens is 18 cm. An object 5cm high is placed at a distance of 12 cm from the lens. Determine the position, nature and the height of the image (2018) ( Hint: Formula = 1/f = 1/p + 1/q and height: hi/ ho = p/q )
Note: No question in 2009
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Notes By Practical Center
