question_answer

  An electric iron consumes energy at a rate of 840 W when heating is at the maximum rate and 360 W when the heating is at the minimum. The applied voltage is 220 V. What is the value of current and the resistance in each case?

Answer:

                  We know that the power input is P = VI Thus, the current, When heating is at the maximum rate, and the resistance of the electric iron isWhen heating is at the minimum rate, and the resistance of the electric iron is                                 (1)