Question

You have been attending an interview for the Engineer position at XYZ company. One of
the interviewers asked you: “There are two different circuits which differ in its connection
(series and parallel) and both of the circuits consist of a battery and two LED lights. Assume
that both LED lights and battery are having an equal resistance and potential difference,
respectively. By applying any circuit rules that you have learned during your undergraduate
course, state which battery runs out of power first? Justify your answer by obtaining the
power in both circuits.

Answer 1

see in the image two circuit one is series circuit another is parallel circuit.

Total resistance (Requirement) of the series circuit is greater than of total resistance of parallel circuit so power consumed by the series circuit is less than the parallel circuit because Power consumed by any circuit is = V^2/R. Thererfore more resistance less power cosumtion and vice varsa(here supply voltage(V) is constant). So, which battery is connected with the parallel circuit will be run out first.

Due to more resistance current will be less and less power will be drawn (P=I^2*R). In parallel circuit current is high due to less resistance (from series circuit resistance) so power consumed by parallel circuit is greater than series circuit. Therefore battery connected with parallel circuit will be run out first.