What is the Total Resistance of the Combination? - Physics

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Numerical

Three resistors 2 Ω, 4 Ω and 5 Ω are combined in parallel. What is the total resistance of the combination?

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Solution

There are three resistors of resistances,

R1 = 2 Ω, R2 = 4 Ω, and R3 = 5 Ω

They are connected in parallel. Hence, total resistance (R) of the combination is given by,

`1/"R" = 1/"R"_1 + 1/"R"_2 + 1/"R"_3`

= `1/2 + 1/4 + 1/5`

= `(10 + 5 + 4)/20`

= `19/20`

∴ R = `20/19` Ω

Therefore, the total resistance of the combination is `20/19` Ω.

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Chapter 3: Current Electricity - Exercise [Page 127]

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NCERT Physics Class 12
Chapter 3 Current Electricity
Exercise | Q 3.4 (a) | Page 127
NCERT Physics Class 12
Chapter 3 Current Electricity
Exercise | Q 4.1 | Page 127

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