Wednesday

April 23, 2014

April 23, 2014

Posted by **Lizette** on Friday, October 12, 2007 at 1:50am.

- science -
**chanell**, Friday, October 12, 2007 at 4:18amletter B

- science -
**Dr Russ**, Friday, October 12, 2007 at 8:26amYou haven't stated the third resistance, but both A) and B) are not possible for any value in parallel with two 20 ohm resistors. The only possible answers are C) and D).

using 1/R(total) = 1/R +1/R +1/R

1/20 +1/20 =0.1

if the unstated value =x

A)

so 0.1 +1/x = 1/20 = 0.05

which requires a -ve value for x

B)

so 0.1 + 1/x = 1/12 = 0.0833

which requires a -ve value for x

C)

so 0.1 + 1/x = 1/8 = 0.125

which requires a value for x=40 ohms

D)

so 0.1 + 1/x = 1/5 = 0.2

which requires a value for x=10 ohms

**Related Questions**

Science - There Are Three Resistance In A Parallel Circuit. Two Of Them Are ...

science - There are three sources of resistance in a parallel circuit. Two of ...

SCIENCE - THERE ARE THREE SOURCES OF RESISTANCE IN A PARALLEL CIRCUIT,S . TWO OF...

Physical Science - Hello, Can someone tell me if I have the correct answer? ...

Electricity and Electronics - A circuit contains twodevices that are connected ...

Physics - I'm totally confused and this is due Monday- We're dealing with ...

Algebra 2 - two resistors are connected in parallel. Their resistances are 8 ...

Algebra 2 - two resistors are connected in parallel. Their resistances are 6 ...

Pre-Calc - Hello, I am not sure how to go about solving this equation: The total...

Engineering Science (Physics) - A platinum coil has a resistance of 3.146(ohms) ...