• # question_answer A coil takes 15 min to boil a certain amount of water, another coil takes 20 min for the same process. Time taken to boil the same amount of water when both coil are connected in series                                  [DCE 2005] A)            5 min                                        B)            8.6 min C)            35 min                                      D)            30 min

Time ${{t}_{S}}={{t}_{1}}+{{t}_{2}}=35\,\,\min .$