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SAI INTERNATIONAL SCHOOL

                                                    CLASS - VIII

                                              Subject – CHEMISTRY

                        Chapter – CHEMICAL EFFECT OF ELECTRIC CURRENT

                   TOPIC – LED (Light Emitting Diode), Effects of Electric Current


                                               HOME ASSIGNMENT


        Objective:



        Q. No.                                             Questions
           1.     What happens when electric current is made to flow through a conductor?
                     a)  Some amount of electrical energy is converted into heat energy.

                     b)  Some amount of electrical energy is converted into mechanical energy.
                     c)  Some amount of mechanical energy is converted into electrical energy.
                     d)  Some amount of heat energy is converted into electrical energy.
           2.     What is the principle involved in the glowing of an electric bulb?
                     a)  Magnetic effect of current

                     b)  Heating effect of current
                     c)  Chemical effect
                     d)  Conduction of current
           3.     Why are LED’s extensively used to replace bulbs?
                  1. Consume less electricity         2. Have longer life          3. Have more power
                     a)  Only 1 and 2.

                     b)  Only 2 and 3.
                     c)  Only 1 and 3.
                     d)  All 1, 2 and 3.
           4.     Which of the following effects of current is responsible for the deflection of a compass
                  needle in an electric field?
                     a)  Heating effect of current

                     b)  Magnetic effect of current
                     c)  Conducting effect of heat
                     d)  Chemical effect of current
           5.     Electrode connected to negative terminal of the battery is a/an:
                     a)  Electrolyte
                     b)  Anode

                     c)  Cathode
                     d)  Cell






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