Question

The figure given below shows three resistors? 

 

Their combined resistance is: 

(a) `1 5/7`Ω

(b) `14` Ω

(c) `6 2/3` Ω

(d) `7 1/2` Ω

Answer 1

(d)   `7 1/2`Ω 

The resistors of 6and 2 are connected in parallel 

∴  `1/R=1/R_1+1/R_2` 

Here, 

`R_1=6`Ω

`R_2=2` Ω

`1/R=1/6+1/2` 

`1/R=4/6`

`R=6/4` 

This arrangement is further connected in series with the 6 resistor 

∴Net resistance` =6/4+6=7 1/2` Ω