# Static and current electricity

## Homework Statement

Three resistors, 21, 43, and 73 , are connected in series, and a 0.55 A current passes through them. What is
(a) the equivalent resistance and
(b) the potential difference across the three resistors?

## Homework Equations

i tried to use EPE/q by putting the equivalent resistors/1.6E-6 charge. i dont think this is right though :/

## The Attempt at a Solution

I got a as 137 and that is correct but i cant seem to get part b.

## The Attempt at a Solution

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gneill
Mentor
You want Ohm's Law. Look it up!

v=IR, but how does that help me find potential difference?

gneill
Mentor
v=IR, but how does that help me find potential difference?
What do the variables in the formula represent?

volts=resistance(current)
is potential difference under volts?...because i tried 11*25 but that was marked incorrect by my online homework

gneill
Mentor
Potential difference is given in volts.
Current is given in Amps.
Resistance is given in Ohms.

You have the resistance and the current. Find the voltage.

what is my current?
and do i use the the equivalent capacity as resistance?

(b) each of the three resistors or across all of them together?
If it is the later: delta V = IRtotal

** the current is the same through each of them and all of them (connection in series).

the question just says the potential difference across the three resistors; so i think it might be the total. but i am still confused on which part is the current

gneill
Mentor
the question just says the potential difference across the three resistors; so i think it might be the total. but i am still confused on which part is the current
It is explicitly stated in the problem.

"I" is the current.
In your case: 0.55 A i.e. 0.55 Ampere (a unit of electric current).

Your question suggests you need to go back to your notebook/coursebook and reading that chapter again (Ohm's Law in a series circuit) and mostly looking at the examples and the implementation of the law.

good luck.

YYYEESSS!. thank YOU.
also thanks for putting up w/me thru this problem
i was making it harder than it is