Review and Practice

Meausre Current: Self-check

In this activity, you:

• measured the current through a circuit using an ammeter and
• learned about Kirchhoff’s circuit law.
• Were you able to successfully build and measure the current with your ammeter?
• Do you understand the principle of Kirchhoff’s current law?

Questions

1. Should an ammeter be connected in series or in parallel?
2. If you replace one resistor with a larger one, what change would you expect in the current through the circuit?
3. What law has the equation I = V / R?
4. What law has the equation I = I1 + I2 + … + IN?

Exercises

1. Calculate the current through a 100 Ω resistor if the voltage across it is 1 V.
2. Calculate the current through a 1 kΩ resistor if the voltage across it is 2.2 V.
3. If three circuits conducting 1 mA feed into a single circuit, calculate how much current that single circuit conducts.
4. Circuits A and B supply current to circuit C.  The current through A is 5 mA, and the current through C is 9 mA.  Calculate the current through circuit B.

Project

1. Repeat the Your Turn – KCL, but with 1 kΩ resistors.