Two resistors when connected in series net resistance is 5 `Omega` and when they are connected in parallel net resistance is 1.2 `Omega`. What are these resistors ?

Options

A. 2` Omega , 3 Omega`
B. `1 Omega, 4 Omega`
C. `0.6 Omega 0.6 Omega`
D. `1 Omega, 0.2 Omega`

Answer

A

Explanation

2` Omega , 3 Omega`
series connection `R_(1) + R_(2) = 5 Omega` .... (1)
Parallel connection `(R_(1) R_(2))/(R_(1) + R_(2)) = 1.2 Omega " "` .... (2)
By using value of (1) in (2),
`(R_(1)R_(2))/(5) = 1.2 `
`therefore R_(1) R_(2) = 6 " "`.... (3)
From given options , (A) 2 `Omega, 3 Omega` matches with equation (1) and (3) .