Series and parallel circuits

In summary, this conversation revolves around solving several electrical problems involving resistors, voltage, and current. The first problem involves two resistors in parallel, with values of 5 ohms and 20 ohms, connected to a 20 V source. The equivalent current supplied by the source is 80 amps. The second problem asks for the equivalent resistance of two 2 ohm resistors in parallel, which is 1 ohm. The third problem involves a series combination of a 10 ohm and 30 ohm resistor with a 20 V potential, and asks for the current in the 10 ohm resistor. The answer is 1 amp. The fourth problem deals with the number of wires in a 120 V
  • #1
Max CR
121
0
2.Two resistors of 5 ohms and 20 ohms are connected in parallel across an ideal source of 20 V. The current supplied by the source is

a) .4 A, B) 5 A c) 20 A d) 1 A e) none of these

My work
R1 = 5 ohms
R2 = 20 ohms
V = 20 v
I = ?

V = IR
V/R = I = 20 V / 114 ohms = 80 amps


3. Homework Statement [/b]
Two 2 ohm resistors are in parallel. What is their equivilant resistance?

1/2 ohms + 1/2 ohms = 1 ohm. Is this correct?


4)A 20 volt potential is applied across a series combination of a 10 ohm and a 30 ohm resistor. The current in the 10 ohm resistor is a) .5 amps, b) .67 amps c) 1.0 amps d) 2.0 amps

P = I^2R
I = THE SQUARE ROOT OF (R/P)
I = THE SQUARE ROOT OF (10 ohms/20 V)

5) a 120 volt home electrical socket has 3 wires. How many of these wires would give yo ua shock if you were grounded when yo utouched them one wire at a time?

a) one b) two c) three

I think it is one.
 
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  • #2
For 2 you need to use the relationship that

1/Req = 1/r1 + 1/r2

No idea where your 114 came from.
 
  • #3
Woudl anyone mind showing me and hleping me solve these problems?
 
  • #4
Max CR said:
Woudl anyone mind showing me and hleping me solve these problems?

I've already helped you with 2).

Doing the problems for you isn't exactly going to help you learn the material.
 
  • #5
THanks anyways i got help on Yahoo Answers
 
  • #6
Max CR said:
THanks anyways i got help on Yahoo Answers
As long as you get to uplink to Yahoo Answers for your exams you'll be all set then.

Good luck.
 
  • #7
Max CR said:
THanks anyways i got help on Yahoo Answers

Just to be completely scientifically accurate: you mean you got answers at Yahoo Answers. Which is good, I suppose, since that's what the name claims they'll give you.

As LowlyPion said, good luck on your exam.
 

1. What is the difference between a series and parallel circuit?

A series circuit is a circuit in which all components are connected one after another, creating only one path for current to flow. A parallel circuit is a circuit in which components are connected in multiple branches, creating multiple paths for current to flow.

2. What is the effect of adding more components in a series or parallel circuit?

In a series circuit, adding more components increases the overall resistance and decreases the overall current. In a parallel circuit, adding more components decreases the overall resistance and increases the overall current.

3. How does voltage and current behave in a series and parallel circuit?

In a series circuit, voltage is divided between components and the total voltage across all components is equal to the sum of individual voltage drops. In a parallel circuit, voltage is the same across all components and the total current is equal to the sum of individual currents.

4. What happens if one component in a series or parallel circuit fails?

In a series circuit, if one component fails, the entire circuit will stop working. In a parallel circuit, if one component fails, the rest of the circuit will continue to function normally.

5. How are the total resistance and current calculated in a series and parallel circuit?

In a series circuit, the total resistance is equal to the sum of individual resistances, and the total current is the same at all points in the circuit. In a parallel circuit, the total resistance is inversely proportional to the sum of individual resistances, and the total current is equal to the sum of individual currents.

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