• Introduction
• Lesson
• Review & Tasks

Task 1

Use the interactive below to learn more about the relationship between voltage, current and resistance. Notice that with the same voltage, as you increase resistance, current decreases, and as you decrease resistance, current increases. This is called an inverse relationship. We will learn of other inverse relationships when we study pressure and volume in gases.

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1. What are some ways to change the resistance in a circuit?

2. Suppose you have an electrical device that needs a steady current of 10 milliamperes. You need to greatly increase the length of the wire between the battery pack and the appliance. What changes will you need to make in your circuit to keep a steady current?

3. Suppose you are designing a toaster, a device that requires several hot, glowing wires to do its job. You want to use as little voltage as possible. Describe the characteristics of the "toasting" wires.

Submit your completed questions to the 4.03 Voltage Interactive Dropbox.

 

Task 2

Use V = I R, I = V/R, and R = V/I to solve the following problems.

1. Voltage = 3 V, Resistance = 2 ohms, Current = ?

2. V = 6 V, R = 2 Ohms, I = ?

3. V = ? , R = 10 Ohms, I = 2 A

4. V = ? , R = 100 Ohms, I = 5 A

5. V = 110 V, R = ? I = 1 A

6. V = 3 V, R = ?, I =.5 A

7. How much voltage is required to light a 60 ohm light bulb with 2 amps of current?

8. If you power a flashlight with two C cell batteries (1.5 V each), what is the resistance of the light bulb if it draws 0.5 amps of current?

9. How much current flows through a circuit with 1,000 Ohms of resistance and powered by 110V?

10. How much resistance is found in a music player powered by a 1.5 volt battery which draws .001 A of current?

Submit your answers to the 4.03 Voltage Practice Problems Dropbox.