Question

Observations of practical to compare the emf of two given primary cells using potentiometer

Answer 1

The observation for the experiment to compare the emf of two given primary cells using potentiometer are as follows:-

Balancing lengths

L1 for cell E1 in cm                     L2 for cell e2 in cm                 e1/e2=laj1/laj2

327                                              376                                               0.86

323.5                                           371                                                0.87

321.5                                            369                                               0.87

312.5                                            352.5                                            0.88

The precautions that is needed to be taken are:-

• There must be a tight connection.
• The connection should also be neat.
• Only when the observations are taken then only the plugs must be introduced.
• A battery emf  must be  greater than the emf of the cells.