Lab Explained: Ohm’s Law Lab

Research question:

How will increasing the voltage (v) to 5v, 10v, 20v, 35v, and then 50v affect the amount of current (Amps) measured by an ammeter, keeping the resistance (ohms) at 12 ohms and the wire length of 10cm constant, in a series circuit to prove ohms law?

Background information on Ohm’s law:

Ohm’s law can be used to identify the relationship between voltage, current, and resistance in any DC electrical circuit discovered by a German physicist named, Georg Ohm. This law states that voltage is equal to the product of the total current and the total resistance.

The equation for this law is often presented in a triangle where the voltage is on the top, current and resistance are on the bottom with only a line separating them:

In order to find the voltage, you must multiply the current and the resistance, to find the current or the resistance you must divide the voltage by either current (to find resistance) or resistance (to find current).

Hypothesis:

I predict that the higher the voltage, the higher the amount of current will be. I think this because there will be more power distributed throughout the series circuit due to the fact of a higher voltage, indicating that the current would run at a faster pace even with the resistance of 12 ohms. If the voltage is 5 and the resistance is 12 ohms, the current would move at a slower pace and would decrease because the resistance causes that slower pace as a result of using more energy from the battery/voltage.

Variables:

Independent variable: The independent variable is the amount of voltage; 5V, 10V, 20V, 35V, and 50V.
Dependent variable: The dependent variable is the amount of current that is flowing in a series circuit measured in AMPS or A.

Controlled variable:

Materials:

• Battery X1
• Resistor X1
• Ammeter X1
• Wires X7 (use more if needed)
• Switch X1 (optional, I didn’t
  use one as it is not mandatory)

Safety:

When undertaking this experiment for the Ohms law lab report, make sure to take safety precautions to be on the safe side and avoid any danger. Firstly, do not have any liquids around the circuit because if it spills it can cause major issues to the circuit such as creating sparks and or start possibly a fire, this is because liquids increase the conductivity of the electrical flow. Ensure that all loose articles are not hanging from any place in your body like a tie, and if you have long hair, tie it back so nothing is touching the circuit as it can irritate you and can be dangerous.

Lastly, check all the materials are in perfect condition to avoid any dangers that could happen, especially check the battery because if it’s not in perfect condition it can explode and become very harmful.

Method:

Graph

Results Table:

Experiment conclusion:

The data shows that the higher the voltage, then the higher current, meaning that the voltage is directly proportional to the current, which is what Ohm’s law states. This means when the voltage increases, the current will always increase as long as there is no resistance or if the resistance stays the same. For example, in my Ohms law lab report, I increased the voltage from 5v, 10v, 20v, 35v, to 50v while keeping the resistance the same, so the current increased every time the voltage increased.

The law was proven for every trial I performed and this can be shown when dividing the voltage by the current to get the resistance. My hypothesis was correct, in my hypothesis, I claimed that the higher the voltage, the higher the current. As shown above, the voltage is directly proportional to the current. One example from my results is when I increased the voltage to 50v, I then divided that number by the current which was 4.17 to give me the amount of resistance which is 12 ohms.

Experiment evaluation:

The overall experiment went well, and it succeeded in the purpose of the trial, which was how changing the voltage could affect the amount of current flowing in a series circuit while being able to prove Ohm’s law. A weakness in my experiment is my graph of the ohm’s law experiment results. My graph was my weakness in this experiment because the graph should have mentioned the resistance as it is a key fact of proving Ohm’s law.

One improvement I could have done to make the experiment better and get more accurate results was if I had added a voltammeter to the series circuit. A voltammeter would read the amount of voltage that is given out of the battery used, therefore if I used a voltammeter, I could have ensured that the amount of voltage that was given out of the battery was correct and the results would be more accurate.

In conclusion, the Ohm’s law experiment and Ohm’s law experiment results demonstrate the relationship between voltage, current, and resistance, highlighting the principles of Ohm’s law. The Ohm’s law experiment lab report effectively proves the hypothesis and provides a detailed analysis of the data obtained.

William Anderson (Schoolworkhelper Editorial Team)

William completed his Bachelor of Science and Master of Arts in 2013. He current serves as a lecturer, tutor and freelance writer. In his spare time, he enjoys reading, walking his dog and parasailing. Article last reviewed: 2022 | St. Rosemary Institution © 2010-2024 | Creative Commons 4.0

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