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General Knowledge :: Physics

  1. An optically plane surface reflects a beam of light

  2. A.

     As a parallel beam in one direction

    B.

     As diffused beams in all directions

    C.

     As parallel beams in all directions

    D.

     As a diffused beam in one direction


  3. The focal length of a concave mirror with a radius of curvature of 20.0 cm is :

  4. A.

     20 cm

    B.

     5 cm

    C.

     10 cm

    D.

     15 cm


  5. The type of mirrors used in the headlamp of cars is

  6. A.

     Parabolic concave

    B.

     Plane

    C.

     Spherical convex

    D.

     Cylindrical concave


  7. Shaving mirror is

  8. A.

     Convex

    B.

     Concave

    C.

     Plane

    D.

     Parabolic


  9. What changes will happen to a bowl of ice and water kept at exactly zero degree Celsius ?

  10. A.

     All ice will melt

    B.

     All water will become ice

    C.

     No change will happen

    D.

     Only some ice will melt


  11. At what temperature do the Fahrenheit and Celsius scales give the same reading?

  12. A.

     212 degrees

    B.

     32 degreees

    C.

     -40 degreees

    D.

     0 degreees


  13. The temperature of a liquid is 32° F. What is its temperature in Celsius scale?

  14. A.

     32° C

    B.

     0° C

    C.

     100° C

    D.

     212° C


  15. To convert temperature from Celcius to Kelvin scale, you must ________ the given temperature.

  16. A.

     Subtract 273

    B.

     Multiply 273

    C.

     Add 273

    D.

     Divide by 273


  17. 0°K is equivalent to

  18. A.

     273°C

    B.

     – 273°C

    C.

     0°C

    D.

     100°C


  19. In very cold countries alcohol is used as a thermometric liquid because

  20. A.

     Alcohol is a poor conductor of heat

    B.

     Alcohol can be coloured for its level to be seen easily

    C.

     Its freezing point is very low

    D.

     It will not stick to the glass tube