Question

you have one 100 ohm resistor what size resistor must you hook up in parallel in order to have a resistance of 99.0

Answer 1

The resistor to be hooked up must be 9900
`\Omega`

Step-by-step explanation:

Recall how resistors in parallel combine to render an equivalent resistor:

`(1)/(R_e) =(1)/(R_1) +(1)/(R_2)`

So we need to find which resistor (R2) we need to combine in parallel with resistor R1 (100
`\Omega`) in order to obtain an equivalent resistor Re (99
`\Omega`) :

`(1)/(99) =(1)/(100) +(1)/(R_2)\\(9900\,R_2)/(99) =(9900\,R_2)/(100) +(9900\,R_2)/(R_2)\\100\,R_2= 99\,R_2+9900\\R_2=9900\,\,\Omega`