Current on 20 Ohm Resistor: Circuit Homework

In summary, the conversation discussed finding the current on a 20 ohm resistor using given equations and a circuit. The solution involved reducing the circuit and solving for two unknowns. The final answer was provided after making the necessary adjustments.
  • #1
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Homework Statement


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Find the current on the 20 ohm resistor.

Homework Equations


The Attempt at a Solution


Well, I'm fairly positive that the two 10 ohm resistors will transport the same amount of current so:

25V - I*25 - I2*10 = 0
25V + I3*5 - 10*I2 = 0
I = 2*I2 + I3

When I solve using those equations, I get I2 = 1.36 A and I = .45 A (I is double of what it should be).
Could anyone look at my equations and tell me what's wrong?
 
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  • #2
Reduce the circuit as much as possible. You put the 5 ohm and 20 ohm in series already. There is also the 5 ohm and 10 ohm that are in parallel. If you reduce that you will then have a circuit with two loops. Then you will only have two unknowns to deal with.
 
  • #3
Ok, now I've got it, thanks
 

1. What is the purpose of a 20 Ohm resistor in a circuit?

A 20 Ohm resistor is used in a circuit to limit the flow of current and to lower the voltage. This helps to protect sensitive electronic components from damage and ensures that the circuit operates safely.

2. How do you calculate the current through a 20 Ohm resistor?

To calculate the current through a 20 Ohm resistor, you can use Ohm's Law: I = V/R, where I is the current in amperes, V is the voltage in volts, and R is the resistance in Ohms. In this case, the current is equal to the voltage divided by 20 Ohms.

3. What is the relationship between current and resistance in a circuit?

According to Ohm's Law, there is a direct relationship between current and resistance in a circuit. This means that as the resistance increases, the current decreases, and vice versa. In other words, the higher the resistance, the harder it is for current to flow through the circuit.

4. Why is it important to consider the resistance of a 20 Ohm resistor in a circuit?

The resistance of a 20 Ohm resistor is important to consider because it affects the amount of current that can flow through the circuit. If the resistance is too low, there is a risk of too much current flowing, which can damage the circuit. On the other hand, if the resistance is too high, the circuit may not function properly.

5. Can a 20 Ohm resistor be replaced with a different value resistor in a circuit?

Yes, a 20 Ohm resistor can be replaced with a different value resistor in a circuit. However, it is important to make sure that the new resistor has the appropriate resistance to maintain the current and voltage levels in the circuit. Changing the resistance can affect the overall function and safety of the circuit.

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