### Goals

• To experience through hands-on activities how to devise simple electrical circuits, especially those with LED lights
• To become familiar with circuit drawings and commons symbols
• To be proficient at completing simple math equations dealing with simple circuits
• To design a simple circuit to perform a task
• To solder components of the designed circuit

### Step A:  Intro

• As a ‘group’ watch the following movie: How to draw a simple electric circuit
• Next, – ALL students, in your own composition book – redraw the most common symbols you’ll be using in your circuits. See here
• In all of your composition books, define the following terms:
• Circuit
• Conductor
• Open and Closed circuit
• Series circuit
• Parallel circuit
• Voltage
• Amperage
• Watts
• Resistance

### STEP B:  Snap Circuits Rules

• You will be in groups of 2.
• Each kit contains all the parts your group will need to complete the activities
• At the beginning of the period pick up your assigned kit and at the end have the teacher check your kit before putting away.
• All group members are expected to use the kits with gentleness and care and keep all the parts organized
• With your assigned Snap Circuit kit, build the circuits listed below – in order.  Carefully ready all directions/explanations

### Step C:  Snap Circuit Projects

Complete #1 on page 8. Answer the following questions and show the teacher your finished circuit.

• What’s the difference between an open and closed circuit. Explain/show the teacher
• In each of your composition books, sketch the circuit, label it #1, and label it series or parallel

Complete #7 on page 11. Answer the following questions and show the teacher your finished circuit.

• What’s the purpose of the ‘resistor’ in this circuit?
• What is the ‘ohm’ rating for this resistor?
• In each of your composition books, sketch the circuit, label it #7, and label it series or parallel

Complete #8 on page 11. Answer the following questions and show the teacher your finished circuit.

• What happens when you turn the diode the other way?
• In each of your composition books, sketch the circuit, label it #7, and label it series or parallel

Complete #102 – Batteries in series. Answer the following questions and show the teacher your finished circuit

• What is the voltage of one of the battery packs?
• What is the voltage of the other?
• When it’s in the circuit, what’s the voltage?
• Show the finished experiment with 2 battery packs and then with 1 battery pack. Why doesn’t the LED light with only 1 battery pack?

From the following website: https://learn.sparkfun.com/tutorials/light-emitting-diodes-leds

• Define Polarity and explain why this is important to know
• What does LED stand for?
• Why it’s important to limit the amount of current flowing across the LED and HOW do you limit this current?
• What is ‘Forward Voltage” and what’s important to know about it?

Complete # 153 Parallel Lamps: be able to answer the following questions:

• What’s the main message of this experiment?
• In each of your composition books, sketch the circuit, label it #7, and label it series or parallel

Task A:  Watch and Do: Before starting, with a multimeter, check the voltage of each batter.  How to Build a Simple LED Circuit – However, do the math for 4.5 volts or 3.6 volts instead of 9.  Show the math in your composition books. Show the working circuit when completed.  Materials needed: Ask the teacher for: breadboard, LED’s, resistor, and batteries

Task B:  Watch and Do:  Before starting, with a multimeter, check the voltage of each battery. How to Connect Multiple LEDs in Parallel.   However, do the math for 4.5 volts or 3.6 volts instead of 9.  Show the math in your composition books.  Show the working circuit when completed.  Materials needed: Ask the teacher for: breadboard, LED’s, resistor, and batteries

Engineering Brightness Project