Stevie asked in Science & MathematicsPhysics · 2 months ago

# Can you solve this resistor physics question?

What resistance must be placed in parallel with a 184- resistor to make the equivalent resistance 119?

Relevance
• 2 months ago

(184*119)/(184-119)=337Ω

336Ω .5% resistor  or 340 .5%

• Andrew Smith
Lv 7
2 months agoReport

Note that a 5% tolerance in the 337 ohm resistor gives 2% variation in the combination. ie 117<R<121 ohm.. If you were to choose from standard values a 330 ohm 5% resistor is the closest that you could obtain from the common 5% range.

• oubaas
Lv 7
2 months ago

119 = 184*R / (184+R)

21896 = R(184-119)

R = 21896 / (184-119) = 336.9 ohm

• Sky
Lv 7
2 months ago

One way to write the parallel resistance formula is (R1 x R2)/(R1+R2)

So, for the mystery resistance R, write it as (184 x R)/(184+R)=119

Solve for R.  If you understand algebra, this is easy.

The usual parallel resistance formula is:

1

------------------------------

(1/R1)+(1/R2)+(1/R3)...

So, if you write

1

------------------   = 119  and solve for R, you'll get the same answer.

(1/184)+(1/R)

Source(s): I once tutored algebra
• 2 months ago

I can also

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