Find the resistance of the lamp

The fraction of the battery's energy is the answer.In summary, the problem involves two batteries with their positive terminals facing the same direction inserted in series into a flashlight. The batteries have different internal resistances and when the switch is closed, a current is produced. The task is to find the resistance of the lamp and the fraction of energy transformed into internal energy in the batteries. Using Ohm's Law, the resistance of the lamp can be easily solved. To find the fraction of energy, the energy consumed by the internal resistance must be computed.
  • #1
shinobi12
16
0

Homework Statement


Two 1.50 V batteries-with their positive terminals in the same direction-are inserted in series into the barrel of a flashlight. One battery has an internal resistance of 0.255 ohms, the other has a resistance of 0.153 ohms. When the switch is closed, a current of 600 mA occurs in the lamp. (a) What's the lamps resistance? (b) What fraction of the chemical energy transformed appears as internal energy in the batteries?


Homework Equations





The Attempt at a Solution


I'm not sure how to start the problem. Please Help.
 
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  • #2
a) By Ohm's Law, V = IR. So you know I, you know V, R is the sum of the two internal resistances and the flashlight so it can be easily solved.

b) Not sure what this is asking exactly.
 
  • #3
For the last part compute the energy consumed by the interal resistance.
 

1. How do I find the resistance of a lamp?

To find the resistance of a lamp, you will need to use Ohm's Law, which states that resistance (R) is equal to the voltage (V) divided by the current (I). In this case, the voltage will be the voltage of the power source and the current will be the current running through the lamp.

2. What is the unit of measurement for resistance?

The unit of measurement for resistance is ohms (Ω). This unit is named after the German physicist Georg Ohm, who first defined the relationship between voltage, current, and resistance.

3. Can I measure the resistance of a lamp with a multimeter?

Yes, you can measure the resistance of a lamp with a multimeter. Set the multimeter to the resistance measurement setting and touch the two probes to the two ends of the lamp. The multimeter will display the resistance value in ohms.

4. Does the resistance of a lamp change over time?

Yes, the resistance of a lamp can change over time. This is due to factors such as the age and condition of the lamp, as well as external factors like temperature and humidity. It's important to regularly check the resistance of a lamp to ensure it is functioning properly.

5. Why is it important to know the resistance of a lamp?

Knowing the resistance of a lamp is important for several reasons. It can help you determine the power consumption of the lamp, ensure it is functioning properly, and troubleshoot any issues that may arise. It is also necessary for properly wiring and connecting the lamp to a power source.

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