Resistance and Power Probelm (again)

In summary, resistance is the measure of how much something resists the flow of electricity and power is the rate at which energy is converted. These two concepts are inversely related, meaning that as resistance increases, power decreases. The main factors that affect resistance and power are the material, length, cross-sectional area, temperature, current, and voltage. They can be calculated using Ohm's Law and the formula P=VI. Understanding resistance and power is crucial in fields such as electricity, mechanics, and thermodynamics, as it allows for the design and improvement of technologies and the prediction and control of material and system behavior.
  • #1
johnson.3131
6
0
A light bulb is wired in series with a 132 resistor, and they are connected across a 120 V source. The power delivered to the light bulb is 23.4 W. What are the two possible resistances of the light bulb?

a. lower value
b. higher value

relevant equations V=I/R and P=(I^2)(R)

attempt at soultion:

23.4=I^2(132)
=.4210

Wrong!


V=I/R
120=I/132
=15840

Wrong!
 
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  • #2
You have two resistors in series (the 'resistor' and the bulb )
What do you know about the current through these two resistors?
What equations do you know for the total resistance ?
 
  • #3


I would like to clarify that the given information is not sufficient to determine the resistance of the light bulb. The power delivered to the light bulb and the voltage of the source are not enough information to calculate the resistance. We also need to know the current flowing through the circuit. Without this information, we cannot accurately determine the resistance of the light bulb.
 

1. What is resistance and power in scientific terms?

Resistance is the measure of how much a material or object opposes the flow of electricity. Power, on the other hand, is the rate at which energy is transferred or converted. In simpler terms, resistance is the obstacle and power is the force that overcomes it.

2. How are resistance and power related?

Resistance and power are inversely related - as resistance increases, power decreases and vice versa. This means that the more resistance there is, the harder it is for electricity to flow and the less power is generated.

3. What factors affect resistance and power?

The main factors that affect resistance and power are the material the conductor is made of, its length, and its cross-sectional area. Other factors include temperature, current, and voltage.

4. How can resistance and power be calculated?

Resistance can be calculated using Ohm's Law, which states that resistance is equal to voltage divided by current. Power can be calculated using the formula P=VI, where P is power, V is voltage, and I is current.

5. Why is understanding resistance and power important in science?

Resistance and power play a crucial role in many scientific fields, including electricity, mechanics, and thermodynamics. Understanding these concepts allows scientists to design and improve technologies, such as electrical circuits and engines, and to predict and control the behavior of materials and systems.

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