Can the Brightness of Light Bulb C be Increased by Cutting a Wire?

In summary, the conversation discusses a problem where the goal is to make light bulb C glow brighter by cutting a wire in the circuit. After considering the formula for current and the methods for parallel and series resistors, it is concluded that it is impossible to achieve this without increasing the resistance of bulb B.
  • #1
devilaudy
7
0

Homework Statement



https://www.dropbox.com/s/8tbqxmeoiulxg7s/Screen shot 2013-03-06 at 7.54.11 PM.png

The three light bulbs A, B, and C do not necessarily have the same resistance. The battery voltage remains constant. Click on a wire to cut that will result in the light bulb C glowing brighter. If it is not possible to do this, click in the target area. Careful, you get only 3 clicks.

Hint: Write out the formula for the current through the bulb and see what happens if one of the resistances goes to infinity. Use the methods found on the pages for parallel and series resistors.

Homework Equations



I=V/R
Resistors in series (Req = R1 + R2 + ...)
Resistors in parallel (1/Req = 1/R1 + 1/R2 + ...)

The Attempt at a Solution



On the picture you can see that there is a "x" on the wire between bulbs B and C. That is where I thought the wire had to be cut since this would remove resistors A and B, but it was wrong. I think it may be impossible to do this, but I only have two attempts left so I want to make sure I do not make a mistake again.

Thank you!
 
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  • #2
If you cut at that point then the circuit won't be closed so there won't be any current.
 
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  • #3
I think the answer is impossible. c is the only one that can be cut out but if you were to cut it out it would increase the resistance of b. This is because the equivalent resistance of two parallel resistors is less then the resistance of the resistors.
 

What is circuit resistance?

Circuit resistance is the measure of the opposition to the flow of electric current in a circuit. It is measured in ohms (Ω) and can be caused by various factors such as the material of the circuit, length of the circuit, and presence of resistors.

How do I calculate circuit resistance?

You can calculate circuit resistance using Ohm's Law, which states that resistance (R) is equal to the voltage (V) divided by the current (I). In other words, R = V/I. You can also use a multimeter to measure the resistance of a circuit directly.

What causes high circuit resistance?

High circuit resistance can be caused by a number of factors such as corroded or damaged wires, loose connections, or the use of resistors in the circuit. It can also be affected by the temperature and material of the circuit.

How does circuit resistance affect the performance of a circuit?

Circuit resistance can significantly affect the performance of a circuit. High resistance can cause a decrease in the flow of electric current, resulting in reduced voltage and power. This can lead to overheating and malfunctioning of the circuit. Low resistance, on the other hand, can cause excessive current flow, leading to a risk of short circuits or damage to components.

How can I reduce circuit resistance?

To reduce circuit resistance, you can ensure that the circuit is properly designed and constructed with appropriate materials. Regular maintenance and cleaning of the circuit can also help prevent corrosion and other factors that contribute to high resistance. Additionally, using larger diameter wires and minimizing the use of resistors can also help reduce resistance in a circuit.

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