Science
Related Questions
You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in Table 9.3.
S.
No.Material Medium Refractive Index 1. Air 1.0003 2. Ice 1.31 3. Water 1.33 4. Alcohol 1.36 5. Kerosene 1.44 6. Fused quartz 1.46 7. Turpentine oil 1.47 8. Benzene 1.50 9. Crown glass 1.52 10. Canada Balsam 1.53 11. Rock salt 1.54 12. Carbon disulphide 1.63 13. Dense flint glass 1.65 14. Ruby 1.71 15. Sapphire 1.77 16. Diamond 2.42 The refractive index of diamond is 2.42. What is the meaning of this statement?
A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.
Find the power of a concave lens of focal length 2 m.