Two sets of Christmas lights are available. For set A, when one bulb is removed, the remaining bulbs remain illuminated. For set B, when one bulb is removed, the remaining bulbs do not operate. Explain the difference in wiring for the two sets.??(a) Two resistors are connected in series across a battery. Is the power delivered to each resistor (i) the same or (ii) not necessarily the same? (b) Two resistors are connected in parallel across a batter. Is the power delivered to each resistor (i) the same or (ii) not necessarily the same.??

Explanation:

Bulbs are nothing but resistors that glow when current passes through them.

In Set A, the bulbs (resistors) are connected  parallely to each other, this means that even if one of the bulbs fuses or removed, the circuit will still be completed and others continue to glow.

And in parallel connection if the resistance of the two resistors are same  powered delivered to each is same.

In Set B, bulbs are in series connection, this means that when one of the bulb is removed or fuses, the circuit will break and other bulbs can not operate.In this situation as well  if the resistance of two resistors is same then the power delivered is same.

see earlier

snell's law

refractve index = sin incidence / sin refraction