Electricity Circles question that's killing me

In summary, the conversation is about a problem with an electricity circuit involving a potential of 200 volts at point P and a question about the potential at point Q. The person asking for help has already used the formula E=IR to find that the current is 20A and the potential from P to Q is 110 volts, but their answer of 310 volts is incorrect. They realize their mistake and the correct answer is 90 volts. They thank anyone who took the time to read their question.
  • #1
Dragons Master
2
0
Heya Folks,

First I would like to apologize for my bad English - I live in Israel and our mother toungue is Hebrew here, I'll try my best though..

Now I don't know how you call what we call Straght-Line Electricity Circles but basically I mean AC just not alternative ;)

Anyways my problem is with the following circle:

http://dgemu.suhost.com/physicu/1.gif
(the url is http://dgemu.suhost.com/physicu/1.gif if you don't see it good).

I'm told that the potential in P is 200 volt and I'm asked what's the potential in Q.

Now I went by the (using $ as sigma):
$E = $I*R
equasion and I found that I is 20A, and then I found out that the potential from P to Q is 110v so I assume the potential in P is 310v - but that answer is wrong..

I'm doing an online test and I only get TrUE of FALSE for my answers and I have no idea what is the correct question and how to get to it.

Any help would be appreciated,
- Ben
 
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  • #2
nvm I guess that was really stupid I should've done -110 and then it's 90 and not 310 - the correct answer is 90 - thanks for anyone who read this topic..
 
  • #3


Hi Ben,

Thank you for reaching out with your question. It seems like you are struggling with understanding electricity circuits and potential difference. I will do my best to explain it to you.

First, in English we call "Straght-Line Electricity Circles" a series circuit or a circuit with only one path for the electricity to flow. This is different from a parallel circuit where there are multiple paths for the electricity to flow.

Now, to solve your problem, we need to understand the concept of potential difference. Potential difference is the difference in electric potential between two points in a circuit. In your circuit, the potential difference between P and Q is 110 volts.

To find the potential at Q, we need to use Ohm's Law: V=IR, where V is voltage, I is current, and R is resistance. In this case, we know the potential difference (V=110V) and the current (I=20A), so we can rearrange the equation to solve for resistance (R).

R=V/I = 110V/20A = 5.5 ohms

Now that we know the resistance, we can use Ohm's Law again to find the potential at Q.

V=IR = 20A*5.5 ohms = 110V

Therefore, the potential at Q is also 110 volts.

I hope this helps you solve your problem. Just remember to use Ohm's Law and understand the concept of potential difference. Good luck on your online test!

 

1. What is an electricity circle?

An electricity circle is a closed path or loop through which electricity can flow. It typically consists of a power source, such as a battery or generator, wires to carry the electricity, and a load, such as a lightbulb, that uses the electricity.

2. How does electricity flow in a circle?

Electricity flows in a circle due to the movement of electrons. Electrons are negatively charged particles that are free to move through conductive materials. In a circuit, the power source provides the energy to move the electrons and the wires act as pathways to carry the electrons to the load.

3. What is the role of a resistor in an electricity circle?

A resistor is a component in an electricity circle that is designed to resist the flow of electricity. It is often used to control the amount of current flowing through a circuit and prevent damage to other components. Resistors are measured in units called ohms (Ω).

4. Can electricity flow in a circle forever?

No, electricity cannot flow in a circle forever. This is because there is always some resistance in a circuit, and as electricity flows, it loses energy due to this resistance. Eventually, the energy will be completely used up and the circuit will stop functioning.

5. How can I test if there is electricity flowing in a circuit?

You can use a multimeter to test if there is electricity flowing in a circuit. Set the multimeter to measure voltage and touch the positive and negative probes to different points in the circuit. If there is a voltage reading, it means that electricity is flowing through that part of the circuit.

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