Refraction

CAREER POINT REFLECTION & REFRACTION 1 MARKS Explain the statement that light provides the means of communication ? Which mirror has a wider field of view ? What is critical angle ? Explain why white light is not dispersed while passing through a hollow glass prism ? Which type of mirror is used in the reflector of search light and street light ? 2 MARKS Define Snells law ? Draw a ray diagram to show a image formed when the object is placed at c in concave mirror ? How is rainbow formed ? Explain that the distance of the image is equal to the distance of object for a plane mirror ? When the ray of light goes from water in the air the critical angle is 49 . What is the refractive index of water ? 3 MARKS Draw ray diagrams when the object is kept at C in front of a concave mirror and at infinity in front of a concave lens ? Find the position of a object to be placed in front of a concave mirror of focal length 20 cm to produce a virtual image of twice the size of the object ? An object is placed at a distance of 40 cm from a concave mirror of focal length of 15cm . If the object is displaced through a distance of 20 cm towards the mirror by how much distance is the image displaced ? Find the position of the object of the object when placed in front of a convex mirror of focal length 20 cm produces a virtual image which is half the size of the object ? Explain that the image formed by a plane mirror is at the same distance as the object ? What do you understand by primary , secondary and complimentary colours ? Give examples ? Find the focal length and nature of the lens which should be put in contact with a lens of focal length of 10 cm so that the power of the combination becomes 5 dioptre . Light of wave length 500nm in air enters a glass plate of refractive index 1.5. Find the a ) speed b) frequency c ) wavelength of light in glass .