How Do You Calculate EMF with Ohm's Law?

In summary, resistance is the measure of how much a material or device impedes the flow of electric current and is measured in ohms. Ohm's Law describes the relationship between voltage, current, and resistance in an electrical circuit. Resistance can be calculated by dividing voltage by current, and factors such as material, length, and temperature can affect resistance. Resistance is crucial in regulating and controlling the flow of current in electrical circuits and can also be used to transform electrical energy into other forms in various devices.
  • #1
predentalgirl1
67
1
1.What is the emf of a battery with a 0.15-ohm internal resistance if the battery delivers 1.5 A to an externally connected 5.0-ohm resistor?








Given that r = 0.15 ohm , I = 1.5 ohm , R = 5 ohm.

By Ohm’s law V = I ( R + r)
= 1.5 (5.15)
E=7.725 V

Is my work/answer correct?
 
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  • #2
Looks good to me.
 
  • #3


Yes, your work and answer are correct. You have correctly used Ohm's law to calculate the emf of the battery in this scenario.
 

FAQ: How Do You Calculate EMF with Ohm's Law?

What is resistance?

Resistance is the measure of how much a material or device impedes the flow of electric current. It is measured in units called ohms (Ω).

What is Ohm's Law?

Ohm's Law is a fundamental relationship in physics that describes the relationship between voltage, current, and resistance in an electrical circuit. It states that the current through a conductor is directly proportional to the voltage and inversely proportional to the resistance.

How do you calculate resistance?

Resistance can be calculated by dividing the voltage (V) by the current (I). The formula for resistance is R=V/I. This can also be rearranged to find the voltage or current if the other two values are known.

What factors affect resistance?

The factors that affect resistance include the type of material, the length and cross-sectional area of the conductor, and the temperature. Materials with higher resistivity, longer lengths, and smaller cross-sectional areas will have higher resistance. Temperature also affects resistance, with most materials having higher resistance at higher temperatures.

How does resistance affect the function of electrical circuits?

Resistance plays a crucial role in the function of electrical circuits. It helps to regulate and control the flow of current, preventing it from becoming too high and causing damage to the circuit components. Resistance can also be used to transform electrical energy into other forms, such as heat, light, or sound, in devices like heaters, light bulbs, and speakers.

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