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Two resistors, R 1 and R 2 , are connected in parallel. R 1 =35.0 ohms, and the equivalent resistance of the combination is 14.5 ohms. What is the value of R 2 ? ( unit=ohm)

User Nonsleepr
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1 Answer

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Step-by-step explanation:

Answer:

Step-by-step explanation:

When resistors are connected in parallel combination, then equivalent resistance is given by,


\to \quad \bf{ (1)/(R_1) + (1)/(R_2) =(1)/(R_p)}

Inserting values,


\to \quad \bf { (1)/(R_1) + (1)/(R_2) =(1)/(R_p) } \\ \\ \to \quad \bf { (1)/(35) + (1)/(R_2) =(1)/(14.5) } \\ \\ \to \quad \bf { (R_2 + 35)/((R_2)(35)) =(1)/(14.5) } \\ \\ \to \quad \bf { (R_2 + 35)/(35R_2) =(1)/(14.5) } \\ \\ \to \quad \bf { 14.5(R_2+35) = 35R_2(1)} \\ \\ \to \quad \bf { 14.5 R_2+ 507.5= 35R_2} \\ \\ \to \quad \bf { 507.5= 35R_2 - 14.5R_2} \\ \\ \to \quad \bf { 507.5= 20.5 R_2} \\ \\ \to \quad \bf { (507.5)/(20.5) =R_2} \\ \\ \to \quad\underline{\boxed{ \bf { 24.75 \; \Omega= R_2}}} \\

User Kzotin
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