(b) H-B, W-A, T-A
     (c) H-A, W-A, T-B
     (d) H-A, W-B, T-A
Ans : (b)
182. Copper wires are generally used for electrical power transmission instead of iron wires because: (lFS 1993)
     (a) copper is a better conductor than iron
     (b) copper is cheaper than iron
     (c) copper can take higher power than iron
     (d) copper is lighter than iron
Ans : (c)
183. Who invented the laser? [SSC Graduate 2003]
     (a) Sir Frank Whittle
     (b) Fred Morrisson
     (c) Charles H. Townes
     (d) Seymour Cray
Ans : (c)
184. Match the following:
           Transfer of Heat                          Medium
           A. Conduction                   1.     Polished surface
           B. Convection                   2.     Black surface
           C. Radiation                    3.     Vacuum
           D. Absorption                   4.     Air
                                           5.     A solid medium
            A         B         C          D
       (a)  5         2         3          4
       (b)  5         4         3          2
       (c)  4         1         2          3
       (d)  2         3         4          5
Ans : (b)
185. Consider the following statements: [IAS 2004]
            1) Smart Card is a plastic card with an embedded microchip.
            2) Digital technology is primarily used with new physical communication medium such as satellite and fibre optics
            3) A digital library is a collection of documents in an organized electronic form available on the Internet only.
           Which of the statements given above is/are correct?
       (a)  3 only
       (b)  1 and 2
       (c)  2 and 3
       (d)  1, 2 and 3
Ans : (b)
186. A car is running on a road at a uniform speed of 60 km/hr. The net resultant force on the car is :
       (a) driving force in the direction of car"s motion
       (b) resistance force opposite to the direction of car"s motion
       (c) an inclined force