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प्रश्न
Four resistances of 16 ohms each are connected in parallel. Four such combinations are connected in series. What is the total resistance?
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उत्तर
When four resistors of 16 Ω each are connected in parallel, the effective resistance of the combination can be obtained as:
`1/R=1/R_1+1/R_2+1/R_3+1/R_4`
or `1/R=1/16+1/16+1/16+1/16`
or `1/R=4/16`
or `1/R=1/4`
or `R=4`Ω
The effective resistance of combination is 4 Î.
When four such combinations are connected in series, the effective resistance becomes:
R = R1 + R2+ R3 + R4
R = 4 Î + 4 Î + 4 Î + 4 Î = 16 Ω
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