# PHY ```Winter break Home-Work
Physics
1. Draw a ray diagram showing refraction from denser to rarer medium?
2. The rays, parallel to the principal axis, of a spherical mirror, actually meet at a point 20 cm distant
from its pole. Identify the mirror and give its focal length.
3. Which mirror has a wider field of view? Why?
4.State Snell’s law of refraction? Light enters from air into diamond which has a refractive index of
2.42.Calculate the speed of light in diamond. The speed of light in air is 3.0x 108 m/s.
5. The image of an object at a distance of 20 cm from a mirror is formed at the object itself.
1) Identify the mirror 2) size of the image 4) the focal length of the mirror.
6. An object is placed 50 cm from a lens which produces a virtual image at a distance of 10 cm in
front of the lens. Draw a diagram to show the formation of image and calculate the focal length of
the lens.
7. Draw a schematic diagram of Human eye and explain the working of ciliary muscles and eye lens?
8. What are defects of vision? Name. How can these defects of eye be corrected? Illustrate your
answer by drawing a ray diagram to show the formation of image by using corrective lens?
9.What is the power of a lens having a focal length of a) 50 cm b) -50cm?
10. What happens when a ray of light passes through the optical centre of a lens? List out the uses of
convex lens.
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