# Ohm S Law Phet Simulation

Name: ______

Date: ______Period: ______

**Ohm’s Law PhET Simulation**

Link: In the search box, type in “Ohm’s Law”, click on it, and then open in HTML 5.

Purpose:To investigate the relationship among current, voltage and resistance.

**Procedure:Read all directions carefully. Do not calculate missing values for the data tables below; take your data from the simulation itself. **

Part A: Voltage is set at 4.5 and Resistance is set at 500 Ω

- Write down the equation. ______

- How does the size of the current (I) compare to the size of the Voltage and Resistance? ______

**Part B: Data Collection: Constant Resistance, Changing Voltage**

In the first experiment, you will change the voltage to see the effect it has on the current. The resistance will stay the same (500 Ω).

Move the Voltage values to those listed in the Data Table 1, and record the current for each setting. Current is recorded in milliamps (mA).

- What happened to the size of the current (I) in the equation as the voltage increased? ______

Data Table 1:

**Constant Resistance (500Ω), Changing Voltage**

Voltage (V) / Current (mA)

1.0

3.0

6.0

7.5

9.0

Data Table 2:

**Constant Voltage (3.0 V), Changing Resistance**

Resistance (Ω) / Current (mA)

99

300

500

800

1000

**Part C: Data Collection: Constant Voltage, Changing Resistance**

In the second experiment, you will change the resistance to see the effect it has on the current. The Voltage will stay the same (3.0 V).

Move the Resistance values to those listed in Data Table 2 and record the current for each setting. Current is recorded in milliamps (mA).

- What happened to the size of the current (I) in the equations as the resistance increased? ______

**Analysis and Conclusions:**

- Make a graph of changing voltage vs. current (Data Table 1). Remember to include all parts for your graph.
- What is the independent variable? ______How was it measured (units)? ______This will be graphed on the ______-axis.
- What is the dependent variable? ______How was it measured (units)? ______This will be graphed on the ______-axis.

- Describe the pattern of the graph. ______
- What effect does increasing the voltage have on the amount of current through a circuit?

______

______

- Is this a direct or inverse relationship? ______
- If the voltage is tripled, the amount of current will be ______.

- Make a graph of changing resistance v. current (Data Table 2). Include all parts to a graph.
- What is the independent variable? ______How was it measured (units)? ______This will be graphed on the ______-axis.
- What is the dependent variable? ______How was it measured (units)? ______This will be graphed on the ______-axis.

- Describe the pattern of the graph. ______
- What effect does increasing the resistance have on the amount of current through a circuit?

______

______

- Is this a direct or inverse relationship? ______

- If the resistance is tripled, the amount of current will be ______.

- What happened to the current when the Resistance was as low as possible (10 Ω)? ______

1