Many years ago a string of Christmas tree lights was manufac

Many years ago a string of Christmas tree lights was manufactured in the form shown in Fig. P2.7a. Today the lights are manufactured as shown in Fig. P2.7b. Is there a good reason for this change? Find I_1, I_2, and I_3 in the network in Fig. P2.8.

Solution

Ans) 2.7

   Yes there is a good reason for this change because ,in series connection as in fig 2.7a if one of the light goes damaged the circuit will be open and all the lights will be turned off and also the total voltage divided among the lights gives rise to less illumination

where in fif 2.7b parallel connection even one of the light damaged remaining lights will work and also each light will receive same voltage and glow with same illumination