(a)     Zero                                          (b)   2 sec (c)   3 sec         ...
(a) Repulsive                          (b) Electrostatic (c)  Conservative                    (d) Non-conservative Answer:  c (8)
(a)     Cavendish                                (b) Copernicus (c)  Brook Teylor                    (d) None of these Answer: a (13)
(a)     Field                                          (b) Force (c)  Intensity                           (d) All of these Answer: d (15)