# Calculate the individual voltage, current and power in series and para

• nickbb12
In summary, the conversation discusses how to determine the voltage, current, and power in a circuit with 16 globes. The speaker calculates the voltage per globe to be 1.5V and the resistance per set of 8 globes to be 15 ohms. They then use the formulas V=IR and P=IV to determine the current and power per globe. Finally, they express confusion about how to determine the voltage drop in a parallel circuit with two strings of 8 globes.
nickbb12
Homework Statement
A set of 16 party lights were purchased for the patio, 2x of 8 sets of bulbs are in parallel with each other, so if i disconnect one bulb, only half of the lights will go out. When all bulbs are functional they draw 3.2Amps from the 24.0V transformer. I need to determine the voltage across each globe, the current through each globe, the power consumed by each globe and finally, if we had a power board with a circuit breaker rated to flip at 10A, how many sets of lights could I operate before flipping the circuit breaker? Thanks :)
Relevant Equations
V = IR
P = IV
V = 24V
I = 3.2A
16 globes (2x 8 in parallel) (8 globes in series)
To determine the voltage I did voltage/number of globes:
24/16 = 1.5V per globe
- Not sure if this is correct or not

To determine current, I figured out using resistance formulas that the resistance for each set of 8 globes is 15 ohms
R = V/I
24/3.2 = 7.5 ohms total resistance
7.5-1 = 2 * 15-1
Each set of 8 has resistance of 15 ohms.

therefore each globe has an individual resistance of 1.875 ohms, I then used I = V/R to get 0.8A per globe.
- Not sure if this is correct or not

To solve power I simply did P = IV,
1.5 x 0.8 = 1.2W
- Again, not sure if this is correct

The last one I'm stumped, no idea how I could figure it out.
Thanks in advance for people who reply :)

nickbb12 said:
To determine the voltage I did voltage/number of globes:
24/16 = 1.5V per globe
- Not sure if this is correct or not
What answer would you have given if all 16 had been in series?
Should it make a difference that it consists of two parallel strings of 8 instead?

Draw a diagram of the circuit, marking the ends with voltages (0 at one end, 24 at the other, say).
If the voltage drop across each bulb is v, what should the difference at the ends be?

## 1. How do you calculate the total voltage in a series circuit?

In a series circuit, the total voltage is equal to the sum of the individual voltages. This means that you simply add up the voltage of each component in the circuit to get the total voltage.

## 2. Can you explain how to calculate the individual current in a parallel circuit?

In a parallel circuit, the individual currents are calculated using Ohm's Law, which states that current (I) is equal to voltage (V) divided by resistance (R). This means that you need to know the voltage and resistance of each parallel branch to calculate the individual currents.

## 3. How do you find the total power in a series circuit?

The total power in a series circuit is equal to the sum of the individual powers. This means that you need to calculate the power of each component using the formula P = VI, where V is the voltage and I is the current. Then, add up all the individual powers to get the total power.

## 4. What is the difference between series and parallel circuits?

In a series circuit, all components are connected in a single loop, meaning that the same current flows through each component. In a parallel circuit, the components are connected in separate branches, meaning that the current is divided between them. Additionally, the voltage remains the same in a series circuit, while it may vary in a parallel circuit.

## 5. How do you calculate the individual resistance in a parallel circuit?

In a parallel circuit, the individual resistances are calculated using the formula 1/R = 1/R1 + 1/R2 + 1/R3 + ... + 1/Rn, where R is the total resistance and R1, R2, R3, etc. are the individual resistances. This means that you need to find the reciprocal of each resistance, add them together, and then take the reciprocal of the sum to get the individual resistance.

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