Two resistors of resistances 6 Ω and 12 Ω, are connected first in series, and then in parallel in a circuit across a battery of 6 V. Calculate the ratio of the heat produced in the series combination to that of the parallel combination of resistors.

0.0136

Explanation:

For the series connection

Effective resistance= 6 + 12= 18 ohm

Current= 6/18=0.33 A

Heat= I^2R= 0.33^2 × 18= 1.96 J

For parrallel

Effective resistance= 6^- 1+12^-1 = 0.167 + 0.083= 0.25 ohm

Current= 6/0.25= 24 A

Heat= 24^2 × 0.25=144J

Ratio of series to parallel= 1.96/144=0.0136

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