SME
Grade 11 Science
Circuits: Ohm's law, series and parallel
The main lesson, then each kind of problem it solves.
Circuits: Ohm's law, series and parallel
Main lesson
Resistors in series
Use this for “A 12 V battery drives 10 Ω and 20 Ω in series. What does the ammeter read, and what is the voltage across each?”
Resistors in parallel
Use this for “40 Ω, 60 Ω and 120 Ω are in parallel on 24 V. Find each branch current, the total current and the equivalent resistance.”
A series-parallel circuit
Use this for “24 V drives R₁ = 4 Ω in series with 6 Ω and 12 Ω in parallel. Find the total current, the voltage across R₁ and each branch current.”
Electric power and energy
Use this for “A lamp on 120 V draws 0.5 A. What is its power and resistance, and how much energy does it use in 2 hours?”